A simpler way to deploy ZIP packages to Azure App Service from the Azure portal
We recently introduced a simpler way to deploy applications to Azure App Service for Linux by uploading a ZIP package through Kudu. The experience lets you review the package contents, choose whether to run a server-side build, and follow the deployment through its different stages. This capability is now available directly in the Azure portal through Deployment Center. To use it: Open your Linux web app in the Azure portal. Go to Deployment Center. Select Manual Deployment (Push). Choose Publish files (new) as the source. Drag and drop your ZIP file or select Browse files. You can now upload and deploy your application without navigating separately to the Kudu site. This is useful for getting started, testing an application, or performing an occasional manual deployment. For repeatable production deployments, we recommend configuring a CI/CD pipeline. To learn more about the deployment experience, including package preview, build options, progress tracking, and deployment logs, see our previous post: A simpler way to deploy your code to Azure App Service for Linux | Microsoft Community HubZero Ops: Agents Operate, Humans Govern
How to design, build, and grow an agentic operations practice — and what becomes possible once you do. A note on scope: the patterns in this guide apply to any agentic operations platform. The specifics — the pricing model, the built-in capabilities, the primitives named throughout — are Azure SRE Agent. Where something is a property of the product rather than a universal truth, it’s called out. Remember when? Remember the 3am page? The one where you sat on the edge of the bed with a laptop balanced on your knees, hunting through six dashboards to work out whether the thing that woke you was even real. Half the time it wasn’t. Remember the cost review? Somebody exports a month of billing to a spreadsheet, three engineers spend a fortnight arguing about which resources are actually orphaned, and by the time you’ve agreed on a plan the next month’s bill has already landed. Remember the zero-day? The all-hands marathon. Two days of people cancelling everything, tracing which services pulled the affected package, hand-patching in an order nobody had time to write down. And remember the CVE backlog — the one everyone knows about, the one that only ever grows, because triaging it properly would take a team you don’t have? None of that was a failure of effort. It was the operating model. For decades it looked like this: humans operated, software assisted. We built dashboards, alerts, runbooks, automation scripts, and eventually copilots — and through every one of those advances, the human was still the operator. That’s the part that’s changing. And it’s genuinely good news. Agents operate. Humans govern. That’s Zero Ops. And the best part is you don’t have to invent it — the path is already well-worn. The five things worth knowing before you start Everything below comes from building and running agentic operations at scale. If you read nothing else, read these. 1. Zero Ops is the destination — and it doesn’t mean zero humans. It means removing operations from humans. People don’t disappear; they move up the stack. They set the intent, govern the system, and validate outcomes. Nobody’s job becomes “watch the dashboard” ever again. 2. The model is not the moat. This was the biggest surprise. The model matters less every year. You can swap models. What you cannot swap is the context and governance wrapped around them. That’s the durable asset you’re building. 3. Context creates intelligence. Agents become genuinely useful the moment they’re grounded in reality — your source code, your live telemetry, your institutional knowledge, your incident history, and the skills and tools to act on all of it. Swap the model and the system still works. Swap the context and it stops being useful. 4. Governance creates trust. Enterprises don’t trust intelligence. Enterprises trust controls. Identity, audit, evals, rollback, evidence. Governance is what earns the right to automate — and it’s liberating rather than restricting, because it’s what lets you say yes. 5. Metrics create permission. Nobody should trust an agent because a demo looked impressive. Trust comes from numbers you can run yourself. If only the vendor can produce the number, it’s marketing. If you can query it, it’s a metric. The climb, and the one thing that changes at each rung Here’s the elegant part. As an agent matures, the thing that changes isn’t how clever it is. It’s what the human reviews. Rung What the agent does What the human reviews Crawl Suggests. A human still does the work. Their own work Walk Does the work one step at a time, asking before each action. Every step Run Completes whole tasks and hands back a change to approve. The diff Fly Fixes, deploys to test, validates the outcome itself, posts the evidence. The outcome And between Run and Fly sits the review wall. When an agent produces hundreds of changes a month, reviewing someone else’s diff is nearly as hard as writing it yourself. That’s where teams plateau — not because the agent isn’t capable, but because the humans became the bottleneck. Fly is how you get past it: you move the unit of human review from the diff to the outcome. Hold that thought — we’ll come back to it, because it’s the most exciting part of the whole journey. Getting there is a design problem before it’s a technology one. Agents that climb were built to climb. So let’s start where every one of them starts — how you scope it, what you teach it, and what you connect it to. Part One — Designing your agent Before you start: what you’ll want in place The good news is that this list is short, and you almost certainly have most of it already. There’s no platform to stand up first. Diagnostic logs turned on for the services you care about. An agent can only reason about what your system actually emits. Telemetry the agent can query. It doesn’t need to live in one place — most estates have it spread across several platforms, and that’s completely fine. What matters is that each of those places is reachable and queryable. This is what turns “something is wrong” into “here’s why.” Read access to the sources that hold the answers — your subscriptions, your repositories, your incident history, your ticketing system. An identity for the agent, with permissions scoped the way you’d scope a new team member’s on day one. A repository for agent artifacts. Skills, custom agents and tool definitions are production code. They deserve version control from the first one. That’s it. Nothing here is agent-specific — it’s the same hygiene that makes a system operable by humans. If your on-call engineer can answer a question at 3am, your agent can too. Step 1: Scope it — how many agents do you actually need? Good news first: fewer than you think. Teams often assume one agent per team, and that’s usually wrong. Five considerations decide it: 1. Fixed cost. Every Azure SRE Agent carries a small baseline charge just for existing — think of it as keeping the lights on so the agent is ready the instant something happens. That means consolidating where you can is genuinely good hygiene: fewer agents, each with a clear job, means every dollar goes toward outcomes rather than idle capacity. 2. Context. This is the big one. An agent is powerful because it holds a complete picture of a system. Split one application’s context across two agents and you’ve halved what each of them knows — usually the half that mattered. Don’t split an app’s context. 3. Data residency at rest. If data legally cannot leave a geography, that’s a boundary, and it’s a real one. Separate agent, separate region. 4. Team and organisational access boundaries. Genuinely different permission sets and genuinely different blast radius deserve genuinely different agents — each with its own identity, so least-privilege actually means something. 5. At least one dev agent. Always keep a non-production agent to test changes before they touch prod. Same reason you have a staging environment. That’s the whole list. Everything else, consolidate. Ideally, this is what it looks like. A single agent per application or product module — never splitting one across two. Explicit production and test agents. A regional agent wherever residency genuinely demands one. Every split maps to one of the five considerations above. The one thing to protect in every split decision is context. When two agents need to reason about the same problem, each one only has half the picture. If you absolutely must split context — say your org structure or access boundaries require it — plan for those agents to talk to each other so the full context is still reachable. Multiple patterns work. A dedicated infrastructure team that manages AKS clusters and only cares about the upkeep of that infrastructure? A single agent scoped to those resources makes perfect sense — they have a clear domain, a clear boundary, and a clear job. An application team whose service depends on a database? Give that application’s agent access to the database rather than standing up a second agent and splitting the problem’s context across two. There’s no single right layout — the principle is: keep the context of the problems you’re trying to solve together. Step 2: Teach it — context is king This is where the magic actually comes from, and it’s the step most worth over-investing in. Your agent needs five kinds of context: Source code — what the system actually does Production telemetry — what it’s doing right now Institutional knowledge — how your team really operates Previous incidents — what broke before, and why Skills and tools — how to act on any of it Connect the first two and you have a competent log reader. Add the middle two and it starts sounding like someone who’s worked on your team for a year. How you actually bring context in: Connect the real sources — subscriptions and their telemetry, your repositories, your incident history, your ticketing system. Knowledge as markdown in a repo. This is the pattern that works best. LLMs are exceptionally good with markdown files, and putting your knowledge in a connected repository means it’s version-controlled, reviewable, and — critically — updatable by the agent itself. Your scheduled tasks can automatically improve these files as the agent learns, closing the loop between insight and artifact. Connect external knowledge via MCP. If your team’s knowledge lives in Confluence, SharePoint, or another platform, connect it as an MCP server rather than migrating it. The agent queries it at runtime. Upload documents. Architecture diagrams, architecture decision records, design docs, onboarding guides. It reads all of it. Just talk to it. This is the underrated one. Tell it how your system works. Explain that “the blue cluster” means the EU stamp, that Tuesday deploys are riskier, that this alert is always noise before 8am. Ask it to summarise your architecture back to you — where it’s wrong, you’ve found a context gap, and you can fill it on the spot. One thing to be deliberate about: don’t dump everything. If you’ve accumulated years of documentation, runbooks, and tribal knowledge, resist the urge to pour all of it in on day one. Garbage in, garbage out. The agent will work with whatever you give it, and outdated or contradictory knowledge makes it worse, not better. Curate intentionally. Start with the knowledge that matters for the scenarios you’re tackling first, make sure it’s current, and grow from there. Teaching an agent feels remarkably like onboarding a sharp new hire. The difference is it reads everything you give it, overnight, and never forgets. And you don’t have to teach it everything at once. This is the part worth saying plainly, because the size of an estate can feel paralysing. You are not trying to pour your entire organisation into an agent before it becomes useful. You teach it the parts that matter, and you do it organically — one solution at a time. Start from your toil. Write down the things that actually wake your engineers up, the tasks your team does over and over, the investigation everyone dreads because it takes four hours and always ends the same way. Pick the top one. Coach the agent through that single scenario the way you’d coach a new engineer through their first on-call shift — the context it needs, the sources it should check, the judgement calls that aren’t written down anywhere. Then do the next one. Each scenario you teach is narrow, which means it’s cheap and fast to get right. And each one compounds: the context you gave it for scenario one is already there when you start scenario three. Six weeks in, you’ll notice it knows your system well enough to help with things you never explicitly taught it. Don’t boil the ocean. Boil the thing that’s burning you. Step 3: Create the artifacts — understand the primitives, then build Before you build anything, it helps to understand the three primitives you’re building with — because the difference between them is what gives you consistency. The meta agent is your agent out of the box. It has the LLM’s world knowledge plus all the context you’ve connected — your code, your telemetry, your documents, your memory. It’s versatile: it can investigate, reason, plan, and act. But it’s non-deterministic. Ask it the same question twice and it might take different steps, in a different order, and format its findings differently. That’s fine for exploration. It’s not fine for the 3am incident that needs to run the same way every time. Custom agents give you that consistency. A custom agent is a specialist with its own instructions, its own tools, and its own scope. Think of it as the what — the plan. The Zava learning lab’s learning-ops agent is a good example: it tells the agent exactly how to handle an incident — what to check, in what order, what to post, how to format the report. Every run follows that plan. Custom agents are scoped — they’re only invoked when you specifically ask for them (via /agent in chat, or via a response plan or scheduled task). That scoping is itself a governance lever, which we’ll come back to in Step 5. Skills are the how. They’re reusable procedures that teach the agent how to do a specific thing — query your Kusto cluster, restart a container app, read an IcM incident, run a particular diagnostic sequence. Skills are universal: both the meta agent and any custom agent can use them. A single skill written once is available everywhere. The key insight: the meta agent alone will get you far, but it won’t do the same ten steps next time, or in the same order, or produce the same kind of report. Custom agents and skills give you that repeatability — and repeatability is what you need for automation you trust. Now — how you actually create them. There are exactly two on-ramps, and which one you take depends on whether you already know the answer. Path A — you have a runbook (a known problem). Throw the runbook at the agent and ask it to build the artifacts: the skill, the custom agent, the tool definitions. Review what it produces, refine it, and have it cut a pull request into your repository. A procedure you’d have hand-written over a week arrives in an afternoon. Path B — you don’t (a complex or unknown problem). Work it interactively. Hand the agent the live problem and investigate together. Let it dig, watch it waver, correct its wrong turns, point it at the source it didn’t know about. When you finally crack it — that’s the moment. Ask it to turn what just happened into a custom agent, a skill, a tool. The next time that problem appears, it’s automatic. Path B is the one people don’t expect, and it’s the more valuable of the two. Your best artifacts aren’t written at a desk. They’re precipitated out of real investigations that worked. Every hard incident you solve together becomes an incident you never have to solve again. This isn’t unusual, either — teams everywhere now run skill-creating skills, agent-building skills, and MCP-server-building skills. Using the agent to build more of the agent is simply how this works now. Step 4: Test it — playground first, then non-prod Treat agent artifacts like code, because they are. Start in the playground — a safe space to exercise a skill against realistic inputs without touching anything. Then promote to a non-production system where the agent can act for real against resources that don’t matter. You won’t get everything right before production, and you don’t need to. Get the critical parts right — the core logic, the safety boundaries, the happy path — and then put it on real work. That’s where you find out what it’s actually like. From there, use evals to improve continuously. Every real run produces one, and reading them is how you find out whether the artifact holds up outside the playground. Part Two covers what to do with that signal — including how to wire it back into the artifacts automatically. And because these are production artifacts, they belong in source control from the beginning — with review, diffs, and rollback. Step 5: Govern it — earn the right to automate Remember principle four: governance creates trust. This is where you make it concrete. Before anything touches production, you decide who the agent is, what it’s allowed to do, what rules gate its actions, and what checks run in context. These controls layer on top of each other, and together they’re what lets you say yes to autonomy with confidence. Identity and access Your agent authenticates as a managed identity — system-assigned or user-assigned — and you scope it with normal Azure RBAC at the subscription, resource group, or management group level. Out of the box, Azure SRE Agent offers two access tiers: Reader — read-only access to your resources. This is all your agent needs for investigation, root-cause analysis, and reporting. It’s the right starting point. Privileged — adds resource-type-specific contributor roles (like Container App Contributor) based on what’s detected in your environment. This is what the agent needs for actions: restart, scale, rollback, configuration changes. Most teams start with Reader and add Privileged only on the resource groups where they want the agent to act. If neither tier fits — maybe you want the agent to restart App Services but never touch network rules — create a custom RBAC role with exactly the permissions you need and assign it to the agent’s managed identity. The agent’s identity is its security boundary; treat it the way you’d treat any other service principal. Run mode This is the single biggest lever. In Review mode, the agent proposes actions and waits for a human to approve each one. In Autonomous mode, it acts on its own within the bounds you’ve set. Most teams start every scenario in Review, watch it work for a few weeks, and then selectively move well-understood scenarios to Autonomous. That graduation is the Crawl-to-Run climb in practice. There’s a third thing worth understanding: what happens when the agent doesn’t have the privileges to act. If the agent’s managed identity lacks the RBAC permission for an action, it doesn’t fail silently — it asks. An Administrator can grant temporary elevation via on-behalf-of (OBO), which lets the action execute using the human’s credentials rather than the agent’s identity. This is the human-in-the-loop pattern at its most precise: the agent does the investigation, proposes the action, and a human with the right privileges authorises it in context. The agent never accumulates permissions it doesn’t need permanently, and the audit trail shows exactly who approved what. Tool controls Every tool the agent has access to can be set to one of three states: Allow — the tool executes without asking. Good for safe read operations you’re confident about. Ask — the tool pauses for human approval before running. Good for actions you trust but want to see before they happen. Off — the tool is completely disabled. The agent can’t use it at all. This is the first governance layer — simple, per-tool toggles. Need the agent to query your Kusto cluster but never write to it? Allow the read tool, turn the write tool off. Need it to restart an App Service but never delete one? Allow the restart, turn delete off. This is how you define the agent’s basic operational envelope. Some actions — like restarting a healthy service or scaling up a container app — may not need any gating at all. Others — like modifying a network security group or changing a database configuration — absolutely do. The right setting depends on how much autonomy you want the agent to have and how much you want a human involved. There’s no single right answer; there’s the answer that fits your comfort level today, and it can change tomorrow. Tool access policies Tool controls are per-tool on/off switches. Tool access policies go deeper: they let you write pattern-based rules that match tool names and even command arguments. Examples: - “Deny any command containing delete “ — bash(az * delete *) matches any az ... delete ... command regardless of which tool executes it. - “Allow all monitoring queries without approval” — so your read-only investigation flow runs uninterrupted. - “Ask before any deployment command” — so deploys always pause for a human. Policies apply at three scopes: Scope Who sets it What it can do Global Admin Allow, Ask, or Deny — across the entire agent Custom agent Admin or author Allow only — widen access within global boundaries for a specific custom agent Thread Any user Allow only — temporary override for one conversation The key principle: a global deny cannot be overridden by a lower scope. A custom agent or thread can widen access but never weaken a global deny. This means an admin can set a floor — “nobody, human or agent, can run a delete command” — and know it holds. Hooks Policies match patterns. Hooks evaluate context. This is the layer that handles the cases patterns can’t express. Four hook events: Event When it fires What you’d use it for Start A new thread begins Seed context, validate the trigger, tag the conversation PreToolUse The agent is about to call a tool Inspect the arguments, allow/deny/ask based on what you see PostToolUse A tool just returned Audit the result, flag sensitive output, trigger follow-up Stop The agent is about to finish Validate that the work is complete, reject and keep the loop running if it’s not Hooks can be prompt-based (an LLM judge evaluates the situation) or command-based (a bash or Python script runs deterministically). They sit at the highest priority in the decision chain — a hook allow overrides everything below it, and a hook deny blocks immediately. Here’s where it gets practical. Say the agent is investigating a performance issue and discovers a corrupt database index. It decides to drop and rebuild the index — exactly what a DBA would do. But you don’t want the agent to ever drop a table. How do you allow one and prevent the other? Three layers, working together: Tool access policy: a global deny on any command matching *DROP TABLE* . Pattern-based, unconditional, always enforced. Custom agent scoping: create a database-maintenance custom agent with instructions that explicitly say “you may drop and rebuild indexes; you may never drop tables.” The custom agent only has the database tools it needs — nothing else. The blast radius is contained by design. PreToolUse hook: a script that inspects the actual SQL command. It allows DROP INDEX , denies DROP TABLE , and can require approval for any DDL command above a risk threshold you define. The policy catches the obvious pattern. The custom agent constrains the scope. The hook handles the edge cases that patterns miss. This is the full stack working together. Scoping automations to a custom agent is one of the most powerful governance levers you have. Instead of giving the meta agent broad database access, you create a specialist with its own tools, its own instructions, its own tool access policies, and its own hooks. The meta agent can investigate and recommend. Actual database changes only happen through the custom agent, with guardrails purpose-built for that domain. Who can configure the agent RBAC extends to the agent itself. Four built-in roles govern who can do what: Role What they can do Administrator Full control — approve actions, manage connectors, configure hooks and policies, change run mode, deploy artifacts Author Create custom agents and tools, upload knowledge, author response plans and incident configurations, manage connectors Standard User Chat, run diagnostics, request actions, create scheduled tasks Reader View conversations and configuration — read-only Separation of duties applies here the same way it applies everywhere else: the person who builds a skill shouldn’t necessarily be the person who promotes it to Autonomous. Only Administrators can approve infrastructure actions — Standard Users and Authors cannot. And only Administrators can create hooks and tool access policies, because those controls govern what every other role can do. How it all fits together These controls layer: identity sets the boundary, run mode sets the default posture, tool controls set the envelope, policies set the rules, and hooks handle the judgement calls. They’re not restrictions — they’re what lets you say yes to progressively more autonomy, with evidence that each step is safe. A useful mental model: governance isn’t a gate you pass through once. It’s the dial you turn up gradually, scenario by scenario, as each one proves itself. The agent that’s fully autonomous for certificate renewals and fully gated for database changes isn’t half-governed — it’s precisely governed. Step 6: Promote to production — your agent configuration is code This is the step that turns your dev agent into a repeatable, auditable production system. Your dev agent is your workshop — the place where you experiment, teach, build artifacts, and iterate until things work. Once they do, the configuration you’ve built there becomes your golden state: the skills, custom agents, tool definitions, knowledge base, response plans, scheduled tasks, and memory that together define how this agent operates. All of it can be declared, versioned, and deployed programmatically: Infrastructure as Code — define agents and their configuration in Bicep or Terraform, same as any other Azure resource. Your agent’s entire shape lives in a template. CLI and REST API — create, update, and configure agents with az commands or direct API calls. Useful for CI/CD pipelines that promote artifacts from dev to prod as part of a normal release. Artifact repositories — skills, custom agents, and tool definitions are files in your repo. Push them to your production agent the same way you push code: through a pipeline, with review, with rollback. This means everything your dev agent learned can flow to production through your existing change process. A new skill gets built and tested in dev, reviewed in a PR, merged, and deployed to the production agent by the pipeline — no portal clicking, no manual replication, no drift. It also means consistency across a fleet. If you run multiple agents — per module, per region, per environment — they can all be powered from the same artifact repository. Update the skill once, deploy it everywhere. The agent-per-module pattern from Step 1 works precisely because IaC makes it cheap to keep them consistent. And when something goes wrong, you roll back the same way you roll back anything else: revert the commit, redeploy the template, and the agent is back to its last known-good state. Step 7: Wire it up — an artifact does nothing until something calls it A skill sitting in your repository doesn’t do anything until it’s bound to a trigger — something in your world that fires it without a human deciding to. It’s an easy step to skip, and worth not skipping. There are three you’ll use constantly: Incident response plans. Attach the artifact to an alert class, so that when that alert fires, that skill runs. This is the single highest-value wiring you can do. Scheduled tasks. For work that should happen on a rhythm rather than in response to a signal — the nightly sweep, the weekly review, the monthly audit. HTTP triggers. For everything else in your ecosystem that wants to start agent work: a pipeline stage, a webhook, a work item transitioning to Ready. Here’s why this matters more than it looks. Remember the climb — Crawl, Walk, Run, Fly. Teams often assume they’ll graduate by making the agent smarter. They won’t. A brilliantly capable agent that only ever runs when someone opens a chat window is still at Walk, permanently, because a human is still initiating every piece of work. Capability doesn’t promote you. Triggers do. Wiring is the actual line between Walk and Run. Cross it deliberately. Step 8: Mimic your production process Here’s the step that turns a clever assistant into an operations teammate: the agent should follow the process your humans already follow. Not a parallel workflow. The workflow. An incident arrives → the agent acknowledges it, so everyone can see it’s owned → it investigates, pulling telemetry, correlating recent deploys, checking dependencies → it posts its findings to the incident, where the on-call already lives → it proposes or applies the mitigation → it updates status → it documents the root cause → it resolves. That’s end-to-end incident investigation and remediation, in the same lifecycle, the same ticket, the same channel your team already watches. No new tool to learn. The on-call engineer just notices the work is already done. And this covers more ground than people expect. Most teams think of incidents in three flavours: outages, where something is down; performance issues, where something is slow or degrading; and manual errors — the config change somebody made by hand at the end of a long day, the setting that got flipped in the portal and never made it back into source control. That third category is the one teams under-count and the one agents are unusually good at, because catching it is mostly a matter of comparing what’s running against what was declared — patient, unglamorous work that nobody wants to do at 2am. A worked example. The Zava learning lab agent runs exactly this loop — incident-triggered investigation and remediation across a live estate. Looking at its real runs: a typical end-to-end run takes about 32 tool calls and lands in a 5-to-12-minute band, with a median around 8.6 minutes from signal to finished work. Roughly five minutes to a mitigation, ten to a full resolution. Compare that with what it replaces: a page, someone waking up, ten minutes to orient, a scramble across dashboards, a colleague pulled in for a second opinion. Ninety minutes and two engineers, on a good night. A second example, from the other end of the lifecycle. A large software vendor running a multi-region estate — dozens of subscriptions, tens of thousands of resources — wired their agents into delivery rather than just incidents. A work item moves to Ready, and that’s the trigger. A custom agent picks it up, writes the code, opens the pull request, deploys the change to a test environment, and runs the validation suite against it — synthetic checks and browser-driven tests, the same ones a human would have run. Then it posts the result on the original work item. The engineer’s first involvement is reading an outcome that already has evidence attached. Same five design considerations from Step 1 govern their fleet: one agent per product module, explicit prod and test agents, and one extra agent in-region purely for data residency. These two examples bookend the same idea. One agent closes incidents; the other closes work items. Both were built the same way — context first, artifacts second, triggers third. Beyond incidents — the agent as a proactive partner It’s easy to think of agents as incident responders, because that’s where the value is most visible. But the best teams use them just as heavily when nothing is broken. Understand your system better. Ask the agent to explain your architecture back to you. Ask it what depends on what. Ask it to map the blast radius of a change you haven’t made yet. Ask it to find every resource in your estate that hasn’t been touched in six months, or every configuration that drifts from what’s declared in code. These aren’t investigations — they’re conversations. And the answers come grounded in your actual telemetry and source code, not a wiki page that was last updated in 2023. Get recommendations you didn’t ask for. Set up a scheduled task that reviews your infrastructure weekly and surfaces opportunities: resources that could be right-sized, SKUs that could be downgraded, replicas that could be consolidated, regions where you’re paying for redundancy you’re not using. The same task can check for reliability gaps: services without health probes configured, storage accounts without soft-delete enabled, deployments running without a rollback path. The agent sees all of it because it already has the context — it just needs a reason to look. Run proactive reliability reviews. Ask the agent to evaluate your service against the Azure Well-Architected Framework, or against your own best practices checklist. Ask it to compare your production configuration against your staging configuration and tell you what’s different — and whether the difference is intentional. Ask it to trace a customer-facing flow end to end and identify the single points of failure. Shift from reactive to preventive. This is the compounding value of the platform. Every incident the agent resolves teaches it something about your system. Over time, the agent that started as an incident responder becomes the thing that prevents incidents — because it’s seen enough of your system to spot the preconditions before they become symptoms. The cost analysis that catches the runaway resource before finance does. The capacity check that raises the quota before the 429s start. The configuration audit that catches the drift before it becomes an outage. The agent that only responds to incidents is useful. The agent that also prevents them is transformative. Part Two — Running it well Two loops, not one queue Once agents are working real incidents, the question stops being can it and becomes which ones. Make that a routing decision rather than a judgement call. Run two loops: an agent loop and a human loop. Every incident class is registered to one of them, so where an incident lands is a property of the class, decided in advance — not something someone works out at 3am. Promotion between loops is deliberate. Moving a class into the agent loop is a reviewable change with a written gate, and a written demotion trigger for when it stops earning its place. The safety net belongs to the incident system, not the agent. Define the conditions your process cares about — not acknowledged within x minutes, not mitigated, not handed off — and let the incident system escalate to the human loop when they’re breached. An agent that has stalled can’t be relied on to report that it has stalled; something outside it has to notice. And escalation should carry the work with it, so the human arrives to evidence already gathered rather than a blank page. Cost: know what an outcome costs One of the quietly wonderful things about agentic operations is that you can finally price an outcome. Agents consume metered units, and every unit maps to work. So instead of “what does our on-call cost?” — a question nobody has ever answered honestly — you get: this incident, end to end, cost this much. For the loop above: an entire incident investigated, mitigated, documented and resolved, in minutes, for under $30. Now price the alternative. Two engineers, ninety minutes, out of hours, plus the context-switch tax on whatever they were doing, plus the meeting the next morning to explain what happened. You’re comparing tens of dollars against hundreds — and that’s before you count the ninety minutes of customer impact that didn’t happen because the fix landed in eight minutes instead of an hour and a half. Multiply by your monthly incident volume and it stops being a cost conversation and starts being a capacity one. The question isn’t “can we afford this?” — it’s “what do we do with the engineering time we just got back?” But be careful not to measure the return only in money and minutes, because the larger part of it never shows up on an invoice. It’s the engineer who slept through the night. It’s the on-call rotation people stop quietly dreading, and the weekend that stayed a weekend. It’s the postmortem that never had to be written — and with it, the whole uncomfortable ritual of working out whose change it was — because the problem was caught and fixed while it was still one degraded instance rather than a customer-visible outage. Teams feel that long before finance notices the bill. Morale has always been a reliability metric; it just never had a dashboard. A few practical habits: - Set a consumption budget deliberately, and know who can raise it and how fast before you need them. - Watch cost per resolved outcome, not total spend. Total spend rising while cost-per-outcome falls is exactly what success looks like. - Use the right trigger for the job. Incident response plans and HTTP triggers bring the work to the agent the instant it matters. Scheduled tasks handle the work that belongs on a rhythm — the nightly sweep, the weekly review. Both have a place; the key is matching each scenario to the trigger that fits it. Live Reports — the UI beyond chat Most people first encounter their agent in a chat window, and chat is genuinely good for investigation and conversation. But it’s not the only surface — and for a lot of operational work, it’s not the best one. Live Reports are interactive HTML applications built by the agent and hosted on the platform. They call the same tools the agent uses — Kusto queries, Azure CLI, incident APIs, connector tools — and render the results as charts, tables, grids, and interactive controls. They’re not screenshots of a past conversation. They’re live applications that re-fetch data every time you open them. Here’s the part worth understanding from a cost perspective: the agent spends tokens when it builds the report — the conversation where you describe what you want. After that, opening the report calls the tools directly. No LLM is involved, so there’s no ongoing token consumption. Build it once, open it a hundred times, share it with your team — the investment is in the creation, and it pays off every time someone opens it. Think of Live Reports as the place where your agent’s intelligence becomes a permanent, shareable surface rather than a conversation that scrolls away. Scenarios where Live Reports shine: Morning triage view. What happened overnight? Which incidents are open, which were resolved autonomously, which need human attention? A single page your on-call opens at the start of every shift — always current, no queries to run. Agent fleet health. Across all your agents: which are healthy, which have degraded tool reliability, which haven’t run in a week? Per-tool success rates, outcome counts, cost-per-resolution trending. The monitoring dashboard you’d otherwise build in Grafana, except it’s already wired to the data. Governance and compliance. NSG audit results, CVE exposure by service, resource compliance against your policy baseline. The report that used to take two engineers a day to compile — now it’s a page that’s always current. Cost analysis. Per-agent spend, per-outcome cost, consumption trending with visual charts. The data that makes the cost conversation in Part Two actually work. On-call handover. A shift handoff report: what happened during this rotation, what’s still pending, what to watch. Built once, regenerated for every handover. Stakeholder status pages. Service health for leadership or customers — uptime, incident summary, SLA adherence — without exposing the underlying tools or conversations. Interactive explorers. Not just viewing data but acting on it. A compliance report where you can drill into a finding and ask the agent to open a remediation PR, right from the report surface. The pattern is the same every time: you tell the agent what you want to see, it builds the report, and from that point forward the report is a zero-cost, always-current application that anyone on your team can open. It’s the agent’s intelligence crystallised into a surface that doesn’t need the agent to be running. Monitor the agent You’ll want a few different lenses, because each sees something the others can’t: Layer What it gives you Live reports Your measurement dashboard — autonomy by scenario, throughput, tool reliability — refreshed from your own connectors every time you open it Scheduled tasks The agent reporting on itself: a weekly health narrative, and the loops that keep artifacts current Your own observability platform Independent health and reliability monitoring outside the agent — the layer that still works when the agent doesn’t Foundry Control Plane Auto-discovers your SRE agents across the subscription: status, error rate, run counts, plus start/stop/block lifecycle control, governed by normal Azure RBAC Agent 365 Organisation-wide registry, governance and security posture across every agent platform you run. Agent 365 is generally available; SRE Agent integration into it is on the roadmap One field-tested tip: track tool failure rate per tool, not in aggregate. The overall success rate in large estates typically sits above 98%, which is reassuring — but it can mask a single connector that needs a configuration fix. Watching each tool individually lets you catch those early, and the fix is usually straightforward: a stale token, a permission gap, a connector that needs reconnecting. Knowledge, evals and learning — insist on these Context isn’t a one-time setup. It’s a living asset, and it’s the thing that compounds — but only if your platform is built to let it. This is the section where what you’re running starts to matter a great deal, so it’s worth being direct about what to demand. Insist on an agent that learns without being told to. The common failure mode of agentic tooling is that all the good material stays in the chat thread. Someone works a hard problem with the agent at midnight, finally cracks it, and the reasoning evaporates when the tab closes. What you want instead is derived learning: the agent distils what it just worked out — the query that got there, the dead end worth avoiding, the service that behaves nothing like its documentation — and files it as durable, structured knowledge on its own, without anyone remembering to write it down. Azure SRE Agent does this automatically. Every investigation deposits something. What still needs your attention is the round trip to the original source of truth. Derived learning lives with the agent. Your runbook, your architecture note, your alert definition lives in your repository — and that’s the copy your humans read. Wire the automation that pushes a learning back into the original artifact as a pull request, so the knowledge doesn’t quietly fork into two versions. This is the single most valuable piece of plumbing most teams haven’t built yet. Insist on evals that run forever, not once. Evals get widely misread as a pre-production gate: test the skill, it passes, it ships, done. That’s the smaller half of the value. The bigger half is relentless — continuously evaluating the agent’s real runs in production. Did it stay in scope? Did it reach the right conclusion? Did it stop and ask when it should have? Did that skill quietly start failing at step four last Tuesday? Real traffic finds things no test suite will, and it finds them on your actual estate rather than on a fixture. Then close the loop, so eval results become work rather than a report nobody opens. Azure SRE Agent ships this as a first-class loop: scheduled tasks that watch the eval signal, notice the degradation, and act on it. Self-improvement — where it gets fun Which is where something rather lovely happens: the agent starts improving itself. It notices a runbook is out of date and updates it. It sees a skill failing at the same step and rewrites that step. It spots a recurring investigation and proposes a new custom agent to own it. It watches its own eval scores and opens a pull request against the artifact that slipped. Teams run learning-loop agents alongside their fleets, and watchdog agents that review other agents’ work. Every completed task should make the next task easier. That’s the flywheel — and it only turns when all three pieces are present: knowledge that accumulates by itself, evals that keep scoring real work, and automation wired to act on both. Put them together and the system stops being something you maintain and starts being something that maintains itself. Part Three — The Zero Ops journey: the art of the possible Now the fun part. Here’s what each rung actually feels like, across the scenarios teams really run. Crawl — the agent suggests, you do the work You’ve connected context and you’re asking questions. It’s already useful: “Which of these 40 alerts overnight actually mattered?” — and it tells you, with reasoning. At this rung the governance sweep produces its first report: here are your idle resources, here are the network rules that don’t match policy, here are the CVEs you’re exposed to. Just a list — but it’s a list nobody had time to produce before, and it took four minutes. The certificate scan tells you what expires in the next 90 days. The cost analysis names your top ten spenders and why they moved. The change reviewer reads an incoming change request and tells you, in plain language, what it actually touches and what depends on it — the blast-radius analysis somebody used to do by hand in a change advisory board meeting. You still do all the work. But for the first time, you can see everything. Walk — the agent does the work, one step at a time Now it acts, asking before each step. This is where investigation and root-cause analysis come alive. An alert fires and the agent has already pulled the telemetry, correlated the recent deployment, checked the dependency, and posted a probable cause on the incident — before the on-call has finished reading the title. The question responder starts answering “is the EU region healthy?” in your team channel, with evidence. The governance sweep grows a spine: it doesn’t just list the orphaned resources, it recommends what to do about each. The CVE report becomes a prioritised remediation plan. The change reviewer stops describing the change and starts drafting it — the implementation plan, the validation steps, and the rollback procedure, written before anyone approves anything. You approve every step. It feels slow. It is also where you discover exactly what your agent is good at — and every gap you find becomes tomorrow’s artifact. Run — the agent completes whole tasks; you review the change Triggers are wired now — incidents, webhooks, schedules — and work starts without you. This is the rung where the 3am page stops arriving. The alert-class handler takes a whole class end to end: fires on arrival, investigates, applies the safe mitigation — restart, scale up, roll back the release — documents it, resolves it. You read about it in the morning. This is the rung where the word self-healing finally earns its place. It’s worth being precise about what it means, because it’s a phrase that gets stretched: self-healing is when the agent detects a known failure class, decides on the response, and acts on it within bounds you pre-approved. Not “the agent does whatever it thinks best.” The class is chosen by you. The safe actions are enumerated by you. The agent’s contribution is that it does the work at 3am, correctly, without waking anyone — and tells you exactly what it did. And notice that this is granted per alert class, never per service. It’s completely normal for one fleet to run some classes at near-total autonomy while other classes sit at a deliberate zero, because nobody’s ready yet. That’s not inconsistency. That’s the control working. The capacity agent sees the quota curve heading for a wall and raises it before anything breaks. The certificate agent opens the renewal PR on schedule. The maintenance agent handles the planned work that used to eat somebody’s weekend — the scheduled patching round, the index rebuild, the node pool rotation — running it in the window, verifying it landed, and reporting on it. The change agent executes the approved change in non-production, validates it, and raises the pull request and the change record together. The governance sweep stops recommending and starts acting — opening pull requests against your infrastructure-as-code to close the findings it used to just report. The CVE backlog that only ever grew? It starts going down, because something is working it every single day. And the work-item loop appears: a backlog item goes in, a custom agent writes the code and opens a pull request. You review the diff. Which is exactly when you meet the review wall. Fly — the agent proves the outcome, and improves the system Fly is not “the agent can execute.” It’s two much better things. Fly, part one: the agent can prove the outcome is correct. It builds the fix. It deploys it to a test environment. It runs the validation itself — synthetic checks, browser tests, the full suite. Then it posts the evidence. You stop reviewing the diff and start reviewing the outcome. That’s how the wall comes down. Now the work-item loop closes completely: backlog item → code → deploy → tested → evidence posted. The release-safety agent doesn’t just roll back after an incident, it gates the deploy beforehand — validating in test and blocking the bad one. The governance sweep pushes its own fix to production, having proven in test that it works. And your standard changes — the well-understood, pre-approved, thousand-times-executed ones — get carried out in production end to end, validated, and the change record closed with the evidence attached. The change advisory board stops reviewing procedure and starts reviewing outcomes, which is what it always wanted to be doing. Fly, part two: the agent improves the system. It learns from every incident. It improves knowledge, artifacts, runbooks, skills — and its own custom agents. The alert-quality loop turns inward: it notices which of your alerts are chronic false positives and opens PRs to fix the alert rules themselves. Your monitoring gets better while you sleep. The system gets better without a human editing it. And back to where we started That 3am page? A whole class of them doesn’t reach a person anymore. The fortnight-long cost review? A standing job that finds the waste and opens the PR. The zero-day marathon? The agent maps exposure across every service in minutes, patches in test, proves it works, and hands you evidence. The CVE backlog that only grew? Something works it every day, and it shrinks. That’s Zero Ops. Not zero humans — zero operations for humans. Your people set intent, govern the system, and validate outcomes. Everything below that line takes care of itself. The proof We run Microsoft this way. Every number here is queryable — these aren’t product metrics, they’re trust metrics. Today: - 2,500+ Microsoft engineering teams - 5,400+ agents running in production - Median time from alert to mitigation: 4 minutes To date: - 1.47M incidents processed - 221K mitigated autonomously - 1.25M enriched for the on-call engineer - ~1M developer hours saved* In the last month alone: - 480K incidents handled - 91K mitigated autonomously - 32M agent actions executed - 60K deploy-and-validate runs - 97.9% of agent work ran autonomously That last number is the one worth sitting with. Ninety-eight percent of the work happens with no human in the conversation — and the two percent that does reach a person is the two percent that genuinely needs judgement. In closing It isn’t about building a better agent. It’s about building a system that deserves autonomy. Context makes it intelligent. Governance makes it trustworthy. Metrics make it provable. When those three come together — agents operate, and humans govern. And the best news: you don’t have to build this from the ground up. Azure SRE Agent already carries these learnings — the context, the governance, the evidence, and the metrics — so your team can start today. Pick one scenario. Give it context. Teach it your system. Work a real problem with it, and turn what you learn into something that persists. Then do it again next week. Start your Zero Ops journey: aka.ms/sreagent · Resources and community: aka.ms/sreagent/links *AI-calculated estimate, based on a conservative earlier baseline.How to build long-running MCP tools on Azure Functions
Recently, a customer building servers with the Azure Functions MCP extension reached out and asked: How do I handle tools that take longer than the client is willing to wait? This becomes especially relevant when tool calls move beyond simple request/response into multi-step workflows and long-running operations. At the same time, MCP is evolving to address exactly this. The Tasks extension is introduced in the 2026-07-28 release candidate, defining a standard way to model long-running work. In this post, we’ll walk through how to build long-running MCP tools on Azure Functions using Durable Functions , a framework for authoring stateful, long-running workflows as ordinary code, with checkpointing, scaling, and recovery handled automatically. MCP tools today Today, MCP tools are fundamentally request/response: the client issues a tools/call the server returns a result This works well for fast operations, but breaks down when: workflows take minutes execution depends on multiple steps latency is unpredictable In practice, clients enforce their own tool-call timeouts. These aren't standardized by the MCP spec and vary per client, but they're often in the ~30–60 second range. If a tool exceeds that window: In practice, clients often enforce short timeouts. If a tool exceeds that window: the client times out the agent observes a failed call the underlying work may still be running So the core issue is that you have synchronous tool calls don’t naturally model long-running work. The MCP Tasks extension The Tasks extension to address this. With the extension, a server can respond to a tools/call with an asynchronous task handle instead of a final result, and the client drives the lifecycle from there: tasks/get: poll the task's status tasks/update: submit input back to the server if the task reaches input_required tasks/cancel: cancel an in-flight task A task carries a status ("working", "input_required", "completed", "failed", or "cancelled") and on completion, the final result. Task creation is server-directed: the client advertises support by including the extension in its per-request capabilities, and the server decides per request whether to return a task. A server won't return a task to a client that hasn't advertised support. It's important to note that Tasks rely on ecosystem support. Clients must advertise the extension, and MCP SDKs must implement the task lifecycle, before servers can use it. So while Tasks is now a defined extension, broad client and SDK support is still in progress. Implement long-runng tasks with Durable Functions today Until the Tasks extension is broadly supported across clients, we need a pattern that works with existing request/response clients and supports long-running execution. The following samples show how, using Durable Functions: Python NET The long-running work in this sample mines a short chain of blocks. Each block requires solving a computational puzzle where the system keeps trying different inputs until it finds one that produces a result matching a specific pattern (for example, starting with a certain number of zeros). Because this involves lots of trial and error, it naturally takes time, making it a good example of a long-running workflow. The server in the sample exposes two tools: start_mining Starts a Durable Functions orchestration to mine the blocks Waits briefly (within a configurable budget) Returns result inline if completed within budget OR returns workflow_id if still running get_mining_result Takes the workflow_id Returns the current state, e.g. "completed", "running", "failed", or "not_found" To ensure that the agent calls the tools in the right order, workflow_id is a required parameter of get_mining_result, so the agent can't poll without starting a mining run first. Also, the "running" response carries a poll_after_seconds and a next instruction, ensuring the agent to poll again if work is not done rather than give up or assume completion. Even so, the poll path still relies on the agent correctly remembering, and not hallucinating, the workflow_id it was handed. If it garbles or invents an id, the poll lands on the wrong instance or none at all (which is why get_mining_result returns "not_found" rather than guessing). What changes with the Tasks extension Once the Tasks extension is fully implemented across clients and SDKs, the model becomes simpler and more reliable: the server returns a Task handle, the client manages the polling and lifecyle calls, and the SDK tracks execution state. This removes a key limitation of today’s solution, which requires the agent to remember and correctly pass identifiers like workflow_id. Call to action Try out the sample and let us know whether it addresses your MCP needs around long-running or workflow type tools!A Better Way to View Logs in Kudu for Azure App Service on Linux
Logs are often the fastest way to understand what is happening inside your application. Whether you are investigating startup behavior, runtime errors, failed requests, dependency issues, or unexpected application behavior, having the right log view can make troubleshooting much easier. To make this easier, we have added a new Log stream page in Kudu for Azure App Service on Linux, available under the Logs dropdown. This experience gives you a single place to stream, browse, search, and filter logs so you can understand what is happening in your app faster. Opening the Logs page You can open Kudu from the Azure portal: Go to your App Service. Select Advanced Tools. Click Go. You can also open Kudu directly by going to: https://<app-name>.scm.azurewebsites.net From there, open the Logs page. View live logs across your app and platform The Logs page lets you view logs as they are being written, with filters for timeframe, instance, container, log type, and level. This helps when you want to focus on a specific instance, look only at errors, or separate application logs from platform events. For example, you can use platform logs to understand container lifecycle events, restarts, startup behavior, warmup probe activity, and other platform-side events related to your app. Quickly find the log entries that matter You can use keyword search to narrow down the log stream or historical logs. This is useful when you are looking for a specific error message, request path, exception, dependency failure, timeout, or any application-specific keyword. Instead of scanning through hundreds of entries, you can search for the terms that are relevant to the issue you are investigating. Investigate issues within a specific timeframe The Log stream page also supports viewing logs for a selected time range. This is useful when you know when an issue occurred and want to inspect both application and platform activity around that time. For example, you can filter to a specific timeframe, switch to Application logs, and check what your app was doing when the issue happened. This can help you troubleshoot scenarios such as failed requests, application exceptions, slow startup, container restarts, dependency issues, or configuration problems. Summary The new Log stream page in Kudu makes it easier to work with logs for Azure App Service on Linux. With live streaming, keyword search, historical views, and filters for application and platform logs, you can quickly narrow down the information you need and troubleshoot issues more efficiently. We are continuing to improve the App Service Linux experience to make diagnostics simpler and more useful for day-to-day development and operations.Introducing Azure Container Apps Sandboxes: Secure Infrastructure for Agentic Workloads
Today we are announcing the public preview of Azure Container Apps Sandboxes - a new first-class resource type that gives you fast, secure, ephemeral compute environments with built-in suspend and resume. This is the underlying infrastructure on which products like Cloud sandboxes in GitHub Copilot, Foundry Hosted Agents, and Azure Container Apps Express are built, you now have the opportunity to build your solutions leveraging this infrastructure. Azure Container Apps Sandboxes unlocks two massive opportunities. For platform developers and ISVs, sandboxes give you the same isolated compute fabric that powers many Microsoft products. You get the building blocks to create your own multi-tenant platform on proven, enterprise-scale infrastructure. For AI agents, sandboxes become a self-configurable tool that lets agents extend their own capabilities on the fly. An agent can spin up a fresh sandbox in milliseconds and use it to execute untrusted code, compile source, test HTTP requests against a live app, launch a browser session, or tackle whatever needs a quick and scalable infrastructure. On one side it empowers humans to build platforms, on the other it empowers agents to build their own capabilities. Both get enterprise-grade isolation, instant startup, and snapshot-based persistence out of the box. We'll walk through the resource model, sandbox lifecycle, the features that set Sandboxes apart - like snapshots, lifecycle policies, network egress controls, volumes, and managed identities - and show you how to get started with the portal and CLI. What Are Container Apps Sandboxes? Container Apps Sandboxes are secure, isolated compute environments that start in sub-second time, scale to thousands, and cost nothing when idle. Each sandbox runs in its own hardware-isolated microVM boundary - fully separated from the host, the platform, and every other sandbox. You bring your own Open Container Initiative (OCI) image, and Sandboxes handle the rest: provisioning from prewarmed pools, strong multi-tenant isolation, and snapshot-based suspend/resume that preserves full memory and disk state across sessions. There are many ways Sandboxes can help you build your next project - here are a few: Your own build & test systems - wire a Sandbox into your CI/CD flow to run builds while your laptop stays cool. Agents that can run anything safely - an agent spawns a sandbox, executes work inside it, and returns the output with no agent host privileges required. Agent swarms - decompose a research question, spawn N sandbox workers in parallel (each pinned to its own image and egress policy), and synthesize the result. Early access customers are already unlocking significant benefits by leveraging Azure Container Apps Sandboxes. "With Azure Container Apps sandboxes, SitecoreAI can safely enable agents to take real action. The combination of multi-tenant isolation, rapid scale-out, and full automation allows Sitecore to run long-lived, autonomous agents that securely execute code, manage workflows, and interact with enterprise systems within secure, governed environments. With this foundation, we can build agents that do real work: assembling content, personalizing experiences, and optimizing campaigns in production. Agents that operate continuously, learn from results, and improve over time, so our customers get better outcomes without giving up control." - Mo Cherif, VP of AI and Innovation, Sitecore "We got early access to Azure Container Apps Sandboxes, and got the first prototype integrated with Atlas AI in hours, and it's already shaping a new Atlas AI capability that we plan to launch in preview in Q3. It gives every Atlas AI agent a safe, sandboxed workspace (file system, terminal, code execution) on a customer's live data in Cognite Data Fusion. The value: Industrial process, reliability, and production engineers spend days and weeks on questions like "which wells are underperforming and why?" These questions are tractable but expensive, so they are asked rarely and decisions are made on gut feel. With this, an agent pulls the data, runs the analysis, cross-references maintenance and inspection records, and returns a cited draft in minutes. Sandboxes make it practical: Aligned feature set, per-customer isolation, pause/resume across multi-day investigations, scale-to-zero economics." - Kelvin Sundli, Product manager, Atlas AI, Cognite Resource Model: Sandbox Groups and Sandboxes The top-level ARM resource is Microsoft.App/SandboxGroups. A Sandbox Group is the management boundary for a collection of sandboxes that share configuration - think of it like a Container Apps Environment, but purpose-built for sandboxes. When you create a Sandbox Group, you specify: Subscription, Resource Group, and Region Sandbox defaults (optional): default CPU, memory, disk, max sandbox count, and default idle timeout Networking: optionally deploy into a custom VNet with a dedicated subnet for private networking Identity: System or user assigned Entra identity. Individual sandboxes are created within a Sandbox Group. Each sandbox has its own source (disk image or snapshot), resource tier, lifecycle policy, network egress policy, environment variables, ports, volumes, and connections. Sandbox Lifecycle Sandboxes have a well-defined lifecycle with the following states: State Description Creating Provisioning the sandbox from a disk image or snapshot Running Actively executing - backed by a live microVM Idle System-suspended after inactivity; can auto-resume on the next request Suspended Full state (memory + disk) preserved as a snapshot; no compute costs Resuming Restoring from a suspended or idle state - sub-second for most workloads Stopped User-initiated stop; can be resumed Stopping Graceful shutdown in progress Deleting Teardown in progress The key insight here is the distinction between Idle and Suspended. When a sandbox goes idle (e.g., no traffic for a configured timeout), the system can automatically suspend it and capture a snapshot. When a new request arrives, the sandbox resumes transparently. This gives you scale-to-zero economics with stateful compute - something that wasn't possible before without significant custom engineering. Disk Images: Bring Your Own Container Sandboxes boot from Disk Images - Open Container Initiative (OCI) images converted into an optimized root filesystem format. You point to any OCI image (public or private registry), and the platform builds a bootable disk image from it. You can start with public, pre-built images maintained by the platform (for example, Ubuntu base images), or bring your own private images. For private registries, you can authenticate with username/token or use a user-assigned managed identity for Azure Container Registry (ACR) – integrated with Azure as you expect. Snapshots: Full-State Persistence Snapshots capture the complete state of a running sandbox - memory, disk, and all running processes. When you resume a sandbox from a snapshot, every process, open file handle, and in-memory data structure is restored exactly as it was. A snapshot captures the full state of a running sandbox: memory pages, disk, processes. Two ways to make one - automatically on suspend, or manually on demand. Three things they're great for: Checkpointing mid-task so a long-running agent can resume exactly where it left off Cloning an environment that's already warm - dependencies installed, caches populated, services running Shipping a "ready-to-go" state that resumes in sub-second instead of cold-booting Snapshots are free during the preview, after which they will be stored as Azure Blob Storage at standard rates. Each snapshot records the source sandbox, resource allocation (CPU, memory, disk), and container metadata - so what you get back is exactly what you snapshotted. Resource Tiers Every sandbox is assigned to a resource tier that determines its CPU, memory, and disk allocation: Tier CPU Memory Disk XS 0.25 vCPU 0.5 GB 5 GB S 0.5 vCPU 1 GB 10 GB M (default) 1vCPU 2 GB 20 GB L 2 vCPU 4 GB 40 GB XL 4 vCPU 8 GB 80 GB When creating a sandbox from a snapshot, the resource tier is inherited from the snapshot and cannot be changed - this ensures the restored environment has the exact resources it was running with when the snapshot was taken. Lifecycle Policies: Auto-Suspend and Auto-Delete Every sandbox can be configured with lifecycle policies that automate state transitions and cleanup: Auto-Suspend Idle timeout: How long a sandbox can sit idle before being suspended (configurable: 1m, 2m, 5m, 10m, 30m, 60m) Suspend mode: Disk + Memory (default): Full snapshot including memory state - resume picks up exactly where you left off, with all processes and in-memory data intact. Disk: Only the disk is preserved; the VM restarts fresh on resume. Useful when you only need file persistence, not process continuity. Auto-Delete Automatically delete sandboxes after a configurable number of days of inactivity Prevents accumulation of abandoned sandboxes that consume snapshot storage These lifecycle policies are what make Sandboxes economically viable at scale. A platform serving thousands of tenants can configure aggressive idle timeouts (say, 60 seconds) with Memory suspend mode, and each tenant's sandbox disappears from the billing meter almost immediately - but resumes in sub-second time the moment they return. Network Egress Policy For scenarios involving untrusted code - AI agents executing LLM-generated scripts, multi-tenant SaaS with user-submitted workloads - controlling outbound network access is critical. Sandboxes provide a per-sandbox Network Egress Policy: Default action: Allow or Deny all outbound traffic Host rules: Domain-pattern rules (e.g., *.github.com → Allow) to permit specific destinations Custom CIDR rules: Network-level rules for IP ranges (e.g., 10.0.0.0/8 → Deny) Skip egress proxy: Option to bypass the egress proxy entirely when custom VNet routing handles policy enforcement This means you can run a sandbox in a deny-by-default posture and allowlist only the specific endpoints it needs (your API server, a package registry, etc.) - without setting up NSGs or firewall appliances. Managed Volumes: Persistent and Shared Storage Sandboxes support two types of mountable volumes, both managed by Microsoft: Volume Type Backed By Best For Managed Azure Blob Azure Blob Storage Shared data across sandboxes, file uploads/downloads, persistent artifacts Managed Data Disk Azure Disk Storage High-performance storage for databases, build caches, large working sets - only available to one sandbox at a time Blob volumes come with a built-in file explorer in the portal - you can browse, upload, download, create folders, and drag-and-drop files directly. Data Disk volumes provide dedicated block storage with configurable sizes. Secrets and Identity Secrets Sandbox Groups support key-value secrets scoped to the group. Secrets can be created, edited, and referenced by sandboxes within the group. These secrets can be used in egress policies to modify requests with transform or header-injection rules, without exposing the secrets to code running inside the sandbox. Managed Identity Sandbox Groups support both system-assigned and user-assigned managed identities, with full RBAC role assignment management. This means your sandboxes can authenticate to Azure services (Key Vault, Storage, Cosmos DB, etc.) without managing credentials - the same identity model you use everywhere else in Azure. MCP Connectors and Triggers ACA Sandboxes now supports managed connectors through the Model Context Protocol (MCP), giving sandboxes access to external APIs - including Microsoft 365, Salesforce, ServiceNow, GitHub, and 1,400+ other systems - without managing credentials directly. Attach a Connector Gateway to your sandbox group, and every sandbox in the group can call external APIs through a standardized MCP interface at runtime. Pair connectors with triggers to build event-driven automation: route an Outlook email to a sandbox that triages it with an AI agent, or react to a SharePoint file upload by extracting and processing the document all without writing glue code. Triggers can fire a shell command inside a sandbox or invoke an HTTP endpoint the sandbox exposes, so your automation shapes fit naturally around your workload. The integration is built on the new Connector Namespace service (az connector-namespace), the same runtime behind Logic Apps and Power Platform connectors, now available as a programmable layer for sandboxes. See the end-to-end samples for runnable azd up-deployable examples covering email triage and document automation scenarios. The Portal Experience Azure Container Apps Sandboxes are only available in the new Azure Container Apps portal that provides a rich, IDE-like experience for working with sandboxes. Creating a Sandbox The portal offers multiple creation paths: Standard Sandbox - full configuration control over source, resources, lifecycle, networking, and volumes GitHub Copilot Sandbox - preset, Copilot CLI ready to go, GitHub credentials can be wired through the Access Token before the sandbox is created Claude Sandbox - Claude CLI pre-installed, ready for agentic coding inside the sandbox Using Coding Agents (Copilot CLI / Claude Code) If you live inside Copilot CLI or Claude Code, you don't need to learn a new CLI. Install the azure-sandbox skill once and your agent picks up the right skills: # GitHub Copilot CLI # Add as a plugin marketplace /plugin marketplace add microsoft/azure-container-apps # Install all skills /plugin install sandboxes@Azure-Container-Apps # Claude Code claude plugin add microsoft/azure-container-apps The skill runs prerequisite checks silently (az --version, az account show, node --version, aca --version), prompts only if something's missing, and maps natural-language asks to the right aca commands. Bundled runbooks cover Copilot CLI BYOK (bring your own Azure OpenAI key), the deploy-a-web-app walkthrough, and shell setup. Sandbox Detail Page Once your sandbox is running, the detail page gives you immediate access to the sandbox terminal and additional details, such as - Network Audit - real-time egress traffic log showing allowed and denied requests Monitor - live CPU, memory, disk, and network utilization charts Connectors - attached connections with an "Add" action Volumes - mounted volumes with an "Add" action Log Stream - streaming container logs Processes - running process list inside the sandbox Files - file explorer to browse the sandbox filesystem The toolbar actions let you manage the state of the sandbox - Resume or Stop. In the Ellipsis menu (⁝) you can find additional settings to manage network Egress Policy and ingress (Add port), take a Snapshot of the sandbox, Commit (save disk state as a new disk image), set Lifecycle Policy or permanently Delete the sandbox. Finally, you can see additional Details in a side panel. Getting Started with the CLI and Python SDK All sandbox and sandbox-group operations go through the aca CLI. There are no az containerapp sandbox commands, - az is only used for az login, az account show, and resource-group management. Install (CLI) # Mac, Linux curl -fsSL https://aka.ms/aca-cli-install | sh # Windows irm https://aka.ms/aca-cli-install-ps | iex Run aca --help to get started. Install (Python SDK) pip install azure-containerapps-sandbox For more details, quick start and examples on ACA CLI and Python SDK, please go to https://sandboxes.azure.com Evolution from Dynamic Sessions If you've used Azure Container Apps Dynamic Sessions, Sandboxes are the next evolution of that capability. Everything Sessions can do, Sandboxes can do - and significantly more: Capability Dynamic Sessions Sandboxes Sub-second startup ✓ ✓ Strong isolation ✓ ✓ Custom container images ✓ ✓ Custom VNet integration ✓ (Partial) ✓ Suspend/resume with Memory and Disk snapshots - ✓ Lifecycle policies (auto-suspend, auto-delete) - ✓ Network egress policy (per-sandbox) - ✓ Persistent managed volumes (Blob, Data Disk) - ✓ Managed identity (system + user-assigned) - ✓ Secrets management - ✓ Configurable resource tiers - ✓ Direct access to sandbox in Portal experience - ✓ We will continue to support Dynamic Sessions, but all new investment goes into Sandboxes. If you're building new workloads on isolated ephemeral compute, start with Sandboxes. How It All Fits Together ACA Sandboxes is a platform primitive. It's the foundation on which multiple Microsoft products are already built - including ACA Express, Cloud sandboxes in GitHub Copilot, and Foundry Hosted Agents. When you build on Sandboxes, you're building on the same infrastructure that powers Microsoft's own portfolio. This is the evolution of what we shared with Project Legion in 2024. Legion described the internal infrastructure; Sandboxes exposes it as a customer-facing primitive that you can use directly. What's Next • Deeper Azure integrations - first-class connectivity with Azure networking, identity, storage, and AI services • Enhanced SDK and CLI - richer programmatic experiences for managing sandboxes at scale • More Microsoft services built on Sandboxes - this is just the beginning Get Started Today • Portal: https://sandboxes.azure.com/ • Documentation: Azure Container Apps Sandboxes • Pricing: Azure Container Apps Pricing (per-second vCPU/memory billing, scale-to-zero, snapshots at Blob Storage rates) We'd love to hear your feedback. You can ask questions, or file issues on the Azure Container Apps GitHub (prefix with [Sandbox] for Sandboxes-specific issues).Designing for High Availability: The Operational Reference for Running a Geo-Replicated ACR
By Johnson Shi, Zoey (Zhuyu) Li, Huangli Wu Introduction Three of the most common questions we hear from enterprise teams running geo-replicated Azure Container Registries (ACR) are: "How do I control which region serves my traffic?" — When my AKS clusters are spread across regions, can I pin each one to its co-located replica, or am I stuck with however the global endpoint routes? "What happens during a regional incident — is failover automatic or do I have to act?" — If the registry in one region degrades, does the global endpoint reroute on its own, or do I need to manually disable the affected replica? "What happens after the region recovers — does traffic return on its own?" — Is there a cooldown, a quarantine, or any manual step before failback? We answer those head-on, then go deeper on the operational details that come up when you actually run a geo-replicated registry: authentication across endpoint switches, throttling under load concentration, eventual-consistency failure modes, home region outage scope, webhooks, and private endpoint interaction. We draw on the official geo-replication docs, the global endpoint health-aware failover blog, the regional endpoints engineering design implementation, the regional endpoints public preview and private preview announcements, and the ACR reference for various registry endpoints, . This post also draws notes from the ACR product team on roadmap items that aren't yet documented elsewhere. Key Takeaways Health-aware failover is automatic. When the registry in a region degrades, the global endpoint reroutes away from it on the order of minutes, evaluated per-registry. No customer action required. Failback is automatic too. Once health-aware failover marks a region healthy again, the global endpoint resumes routing to it. There is no cooldown period. Health-aware failover applies only to global endpoint operations. It does not apply to regional endpoints (you're talking to one replica, period) or to dedicated data endpoints (the redirect is per-region). Health-aware failover is not triggered by throttling. It responds to regional ACR service health and Azure infrastructure health, not HTTP 429 responses. Use regional endpoints to manage per-replica throttling. Regional endpoints (Step 2a) give you explicit per-region URLs for workloads that need affinity, capacity planning, push/pull consistency, troubleshooting, or client-side failover. Use myregistry.<region>.geo.azurecr.io . Regional endpoints are available on Premium SKU registries. For workloads that don't need pinning, do nothing (Step 2b). The global endpoint plus health-aware failover handles routing automatically. Re-authenticate when switching endpoints. Each global or regional endpoint is its own authenticated surface; re-auth via az acr login , SDK auth, or the Kubernetes ACR credential provider on endpoint change. Don't run a long-lived DNS cache for the global endpoint. ACR purges DNS server-side on disable and during failover; a long-lived client cache works against that. For production workloads, enable dedicated data endpoints for security and DNS predictability on layer downloads. ACR is working on bounded staleness consistency for cross-replica eventual-consistency failure modes; see the FAQ. Background What is ACR geo-replication? Geo-replication is a Premium SKU feature that turns a single ACR registry into a multi-region, multi-write service. Every geo-replica in every region is writable — you can push, pull, and delete from any of them — and content syncs asynchronously between replicas under an eventual consistency model. Per-push replication time scales with the size and number of images being pushed. Similarly, when creating a new geo-replica, the time to populate the new geo-replica scales with the total size of the registry. A geo-replicated registry exposes a global endpoint at myregistry.azurecr.io . Behind that endpoint, ACR uses an internal traffic manager to direct each request to the replica with the best network performance profile for the caller — usually the closest replica, but not always. When clients are equidistant from multiple replicas, or when the closest replica is experiencing Azure infrastructure degradation, requests may be routed elsewhere. A geo-replicated registry also exposes a regional endpoint at myregistry.<region>.geo.azurecr.io , which allows clients to pin API requests to a specific geo-replica in lieu of global endpoints, which has Azure-managed routing among geo-replicas. Zone redundancy is always enabled for geo-replicas in regions where Azure has multiple availability zones — in those regions, ACR automatically spreads replica data across multiple availability zones within each region to protect against zonal outages. Endpoints and data endpoints: what goes where A common point of confusion: when you push or pull, not every request goes to the same place. The registry endpoints (global endpoint and regional endpoints), as well as the data endpoint, do different jobs. Your choice of data endpoint configuration has real consequences for security and resilience. Two kinds of traffic flow during a typical pull: Registry API traffic — authentication, manifest reads/writes, tag resolution, referrers, repository operations, blob location lookups, listing, metadata. This is everything except the actual layer (blob) bytes. All these API requests go to the global endpoint ( myregistry.azurecr.io ) or, if you've pinned your clients to call these APIs to a specific geo-replica, a geo-replica's regional endpoint ( myregistry.<region>.geo.azurecr.io ). Behind the scenes, the global endpoint internally proxies these requests to a specific geo-replica. Layer (blob) downloads — when the client asks for a blob, the registry doesn't serve the bytes itself. It returns an HTTP 307 redirect to a regional data endpoint (separate endpoint from the global endpoint or regional endpoints), and the client follows the redirect to download the layer from that region. Where that 307 sends you depends on whether you've enabled the registry's dedicated data endpoints feature: Configuration Layer downloads redirect to Default (no dedicated data endpoints) *.blob.core.windows.net (the underlying Azure storage account) Dedicated data endpoints enabled myregistry.<region>.data.azurecr.io for the region you were routed to Private endpoints enabled myregistry.<region>.data.azurecr.io for the region you were routed to Regional by design. Dedicated data endpoints always land you on a specific geo-replica's data endpoint — there is no "global data endpoint." With the global endpoint as your registry endpoint, the 307 redirect picks the data endpoint for whichever region the global endpoint chose to serve you. With a regional endpoint pinned to a specific region, the 307 always redirects you to that same region's data endpoint — never cross-region. Why dedicated data endpoints matter. Dedicated data endpoints are a Premium SKU feature that exists primarily to address security and firewall scoping. By default, layer downloads redirect to *.blob.core.windows.net — a wildcard storage FQDN. Firewall rules to allow that wildcard either let all Azure storage accounts through or none of them, which raises data exfiltration concerns and isn't tightly scoped to your registry. Dedicated data endpoints replace the wildcard with a fully qualified domain in your registry's own domain — myregistry.<region>.data.azurecr.io — so firewall rules can be scoped tightly to your specific registry, in your specific regions. That same design choice can also make layer downloads more predictable during routing changes. With dedicated data endpoints, the data endpoint FQDN is known ahead of time and lives in the registry's domain — one predictable hostname per region, configured once. Without them, the layer download has to resolve a wildcard storage FQDN that points to whichever storage account the registry happens to have provisioned, which is a separate DNS resolution path with its own routing behavior and its own caching profile. Dedicated data endpoints simplify the DNS picture by aligning the data path with the registry path and keeping the entire pull experience inside one set of predictable, scoped FQDNs. For any geo-replicated registry where security and high availability matter, enable dedicated data endpoints. Note: Health-aware failover applies only to operations against the global endpoint, not to regional endpoints or dedicated data endpoints. Take note that health-aware failover only kicks in and directs traffic away from a geo-replica when an Azure region is experiencing significant infrastructure degradation. At this stage, it does not kick in to redirect traffic to another geo-replica if a client's data plane API requests are throttled. See the relevant section below for the full scope when health-aware auto failover kicks in or not. The three traffic control tools ACR geo-replication gives you three complementary tools for controlling where traffic lands. Each one solves a different class of problem, and customers most often run into trouble when they reach for the wrong one. We name them up front and use these names throughout the post: Tool Who controls it What it does Use cases Health-aware failover Platform (automatic) Reroutes the global endpoint away from a region whose registry can't reliably serve requests Regional incidents, automatic recovery Replica enable/disable for global routing Customer (manual) Excludes a specific replica from global endpoint routing without deleting it; data continues syncing DR rehearsals, planned maintenance, quarantining a replica without losing it Regional endpoints Customer (per request) Dedicated per-region URLs ( myregistry.<region>.geo.azurecr.io ) that bypass the internal traffic manager entirely Pinning AKS clusters to co-located replicas, push/pull consistency, capacity planning, troubleshooting, client-side failover Health-aware failover and replica enable/disable both act on the global endpoint. Regional endpoints are a separate URL surface that coexists with the global endpoint — enabling them does not disable the global endpoint myregistry.azurecr.io . You can use both simultaneously and choose per workload. The behavior in question When the registry in one region experiences a real degradation, there are three possible answers to "what happens?": (A) Nothing automatic. The customer must manually disable the affected region's endpoint to stop traffic from being routed there. (B) The system detects the regional front-door failure and reroutes within seconds. (C) A per-registry health evaluation detects the degradation and reroutes the global endpoint within minutes, with no customer action. After the region recovers, routing resumes automatically. The answer today is (C). Before health-aware failover, customers were stuck closer to (A) — the system could see whether the regional reverse proxy responded, but not whether the registry could actually serve real pull and push traffic end to end. Health-aware failover closes that gap. We walk through all three tools in the next section, in order: setting up geo-replication, using regional endpoints to pin specific workloads, keeping the global endpoint for everything else, the manual replica disable mechanism, re-enabling participation in global routing, and what to expect when health-aware failover triggers. Walkthrough The following steps assume an existing Premium SKU registry and the Azure CLI logged in. We use myregistry as the registry name, myrg as the resource group, and eastus as the home region. Substitute <your-registry> , <your-rg> , and <your-region> for your environment. Prerequisites A Premium SKU ACR registry (geo-replication requires Premium) Azure CLI ( az ) installed and logged in For regional endpoints (Step 2a): Azure CLI 2.86.0 or later. All regional endpoints commands ( --regional-endpoints , az acr show-endpoints , az acr login --endpoint ) are available natively in Azure CLI 2.86.0+. If you previously installed the acrregionalendpoint private preview CLI extension, uninstall it with az extension remove --name acrregionalendpoint to prevent conflicts with the built-in CLI commands. Step 1: Add a West US replica to a registry that lives in East US Geo-replication requires the Premium SKU. The create call below fails on Basic or Standard. # Confirm the registry is Premium az acr show --name myregistry --resource-group myrg \ --query sku.name --output tsv # Premium # Create a West US geo-replica az acr replication create --registry myregistry --location westus # Confirm both replicas are present az acr replication list --registry myregistry --output table NAME LOCATION PROVISIONING STATE STATUS REGION ENDPOINT ENABLED ------ ---------- -------------------- -------- ----------------------- eastus eastus Succeeded online True westus westus Succeeded online True Pushes and pulls continue working through the existing replica throughout initial sync. Because the registry is multi-region, multi-write, the existing replica keeps serving traffic while the new replica catches up in the background. Initial replica seeding time is a function of registry size — the total number and cumulative size of images already in the registry that need to be replicated to the new replica — not the size of any single image. Step 2a: Pin workloads to specific regions using regional endpoints Use regional endpoints when a workload needs explicit per-region control. The five common cases: Regional affinity — an AKS cluster in East US should pull from the East US replica, every time, without ever hopping to a more distant replica because of a network performance fluctuation. Predictable routing — workloads that need to know exactly which replica will serve them, for benchmarking, capacity planning, or in-region traffic SLAs. Push/pull consistency — pinning both ends of a publish-then-deploy flow to the same replica eliminates eventual-consistency races. Troubleshooting — reproducing an issue on a specific replica requires sending traffic to that specific replica. Client-side failover — customers with their own health checks and business rules want to implement failover on their own terms, on signals only they can see. Enable regional endpoints on the registry: az acr update -n myregistry -g myrg --regional-endpoints enabled When enabled, ACR automatically creates per-region login server URLs for every existing geo-replica. No per-region configuration is needed. Note: Regional endpoints can be enabled on any Premium SKU registry, even without geo-replication. A registry without geo-replication has a single geo-replica in the home region, which gets one regional endpoint URL. However, the feature is most useful when your registry has at least two geo-replicas, where you can pin different workloads to different replicas for routing control and capacity distribution. Push to a specific region using its regional endpoint: # Log in to the West US regional endpoint az acr login --name myregistry --endpoint westus # Tag and push using the regional endpoint URL docker tag myapp:v1 myregistry.westus.geo.azurecr.io/myapp:v1 docker push myregistry.westus.geo.azurecr.io/myapp:v1 Pin AKS deployments to their co-located replica by using regional endpoint URLs in the deployment manifest. The example below shows two clusters in different regions; each cluster references the regional endpoint for its own region's replica (assuming replicas exist in both eastus and westeurope ): # East US-based AKS cluster pulls from the East US replica apiVersion: apps/v1 kind: Deployment metadata: name: myapp-eastus spec: template: spec: containers: - name: myapp image: myregistry.eastus.geo.azurecr.io/myapp:v1 --- # West Europe-based AKS cluster pulls from the West Europe replica apiVersion: apps/v1 kind: Deployment metadata: name: myapp-westeurope spec: template: spec: containers: - name: myapp image: myregistry.westeurope.geo.azurecr.io/myapp:v1 This eliminates cross-region pulls when global routing would otherwise prefer a different replica for a given client, and it gives you a per-region traffic profile you can plan capacity against. Regional endpoint operational tips View all endpoints. Use az acr show-endpoints to see all endpoint URLs for your registry — global, regional (if enabled), and dedicated data endpoints (if enabled): az acr show-endpoints --name myregistry --resource-group myrg Import from a specific geo-replica. When importing images between registries, you can use a regional endpoint to import from a specific geo-replica of the source registry. This is useful when you want predictable network paths or need to import from a replica in a specific region: az acr import \ --name mydownstreamregistry \ --source myupstreamregistry.westeurope.geo.azurecr.io/myapp:v1 \ --image myapp:v1 Firewall rules for regional endpoints. If you use firewall rules, allow access to the following endpoints for each geo-replica that clients connect to: Endpoint Purpose myregistry.<region>.geo.azurecr.io Regional endpoint for registry operations myregistry.azurecr.io Global endpoint (if also used) myregistry.<region>.data.azurecr.io Layer downloads (if using private endpoints or dedicated data endpoints) *.blob.core.windows.net Layer downloads (if not using private endpoints or dedicated data endpoints) For the full list of endpoint types and FQDN patterns, see the ACR reference for various registry endpoints. DNS-based routing without changing manifests. If you don't want to maintain different deployment manifests per region, you can keep all manifests pointing to the global endpoint ( myregistry.azurecr.io ) and use software-defined networking or a regional traffic manager to resolve the global endpoint to the appropriate regional endpoint based on the originating region's traffic. This achieves the same co-location goals as regional endpoints — predictable routing and reduced latency — without embedding region-specific URLs in your deployment manifests. Step 2b: Keep using the global endpoint for everything else For workloads that don't need explicit pinning, do nothing. The global endpoint at myregistry.azurecr.io continues to work exactly as before, and the global endpoint plus health-aware failover gives you intelligent routing across replicas without configuration. ACR picks the best replica for each client based on network performance and reroutes during regional incidents. Regional endpoints coexist with the global endpoint — enabling them does not disable myregistry.azurecr.io . You can use both simultaneously and choose per workload, mixing pinned workloads (Step 2a) with workloads that ride the global endpoint (Step 2b) in the same registry. Step 3: Take a replica out of global endpoint routing Use this when you need to keep a replica alive but stop it from serving global-endpoint traffic — for DR rehearsals, planned maintenance, or troubleshooting an isolated replica. # Exclude the West US replica from global endpoint routing az acr replication update --registry myregistry --name westus \ --global-endpoint-routing false Confirm the change: az acr replication list --registry myregistry --output table NAME LOCATION PROVISIONING STATE STATUS REGION ENDPOINT ENABLED ------ ---------- -------------------- -------- ----------------------- eastus eastus Succeeded online True westus westus Succeeded online False Requests to myregistry.azurecr.io no longer route to West US. The replica still receives replicated content — and continues to replicate its own content out to other replicas — and storage quota and per-replica costs continue to accrue. If regional endpoints are enabled, the West US regional endpoint URL also continues to work; --global-endpoint-routing controls only the replica's participation in global endpoint routing. A note on naming. The CLI flag --global-endpoint-routing (on az acr replication update ) and the regional endpoints feature (enabled via az acr update --regional-endpoints enabled ) are two different things despite the similar names. --global-endpoint-routing controls whether a replica participates in global endpoint routing. The regional endpoints feature creates per-region URLs ( myregistry.<region>.geo.azurecr.io ) that bypass the global endpoint entirely. They are independent controls. In Azure CLI 2.86.0 and later, the old --region-endpoint-enabled flag has been renamed to --global-endpoint-routing . The old flag name is deprecated and will be removed in Azure CLI 2.87.0 (June 2026). If you have existing scripts or automation that use --region-endpoint-enabled , update them to use --global-endpoint-routing . CLI flags quick reference: Flag Scope Purpose --regional-endpoints Registry-level ( az acr create or az acr update ) Enables dedicated regional endpoint URLs ( myregistry.<region>.geo.azurecr.io ) for all geo-replicas. --global-endpoint-routing Per-geo-replica ( az acr replication create or az acr replication update ) Controls whether the global endpoint routes traffic to a specific geo-replica. Set to false to temporarily exclude a geo-replica from global routing. --data-endpoint-enabled Registry-level ( az acr create or az acr update ) Enables dedicated data endpoints ( myregistry.<region>.data.azurecr.io ) for layer blob downloads. Auto-enabled when at least one private endpoint is configured. This bidirectional sync during disable is intentional. When you re-enable the replica, every image pushed to the registry while the replica was disabled — from any region — is already present, so the replica can serve traffic immediately with no catch-up window. If we stopped syncing on disable, re-enabling would leave the replica with stale data and force a long catch-up before it could safely serve pulls. Step 4: Re-enable the replica to participate in global endpoint routing Re-enable the replica: az acr replication update --registry myregistry --name westus \ --global-endpoint-routing true NAME LOCATION PROVISIONING STATE STATUS REGION ENDPOINT ENABLED ------ ---------- -------------------- -------- ----------------------- eastus eastus Succeeded online True westus westus Succeeded online True There is no cooldown. The global endpoint resumes routing requests to the West US replica as soon as the change takes effect on ACR's side. Because data continued syncing while the replica was disabled (Step 3), the replica is immediately ready to serve pulls — no catch-up window. Note on DNS during disable/enable. When you take a replica out of global routing, ACR purges its own DNS records for that replica from the global endpoint on a fast path — there is no waiting on a published TTL on ACR's side. If clients run their own DNS cache for the global endpoint, however, those clients will keep resolving to the disabled replica until the client cache expires. We can't control client-side caches. The recommendation: do not run a long-lived DNS cache for the global endpoint. A short-lived DNS pin for the duration of a single push (covered in the DNS and Client-Side Considerations section) is fine and even helpful — but a long-lived DNS cache will make --global-endpoint-routing false look broken from the client's perspective. Step 5: What to expect when health-aware failover triggers Health-aware failover is automatic. ACR evaluates registry health on a per-registry basis, and when a registry in a region can't reliably serve requests, the global endpoint reroutes that registry's traffic to a healthy replica. There is no customer-invocable trigger — that's the point. End-to-end timing is on the order of minutes — fast enough to catch real regional degradation, slow enough to ride out transient errors that resolve on their own. DNS TTL may add additional propagation delay before all clients switch to the new region. Scope of health-aware failover. Health-aware failover applies only to operations against the global endpoint — the registry API calls (auth, get manifest, get tag, get referrers, get blob location). It evaluates health when those API calls come in; it does not trigger mid-operation. Two important consequences: Regional endpoints are not in scope. When you talk to a regional endpoint like myregistry.westus.geo.azurecr.io , you're talking to that one replica. There is no automatic reroute. If you've pinned a workload to a regional endpoint and that region degrades, you implement client-side failover by switching the workload to a different regional endpoint. Dedicated data endpoints are not in scope. Once a registry endpoint has redirected you to a dedicated data endpoint, you stay on that region's data endpoint for the duration of the layer download. There is no automatic reroute of an in-flight blob download. The region targeted by the redirect is decided up front by whichever registry endpoint served the blob-location call: the global endpoint chooses based on its per-registry health evaluation, and a regional endpoint always targets its own region. The signals you can use to confirm a failover is in progress: # Check replication status az acr replication list --registry myregistry --output table You can also check Resource Health for the registry in the Azure portal — navigate to your registry and select Resource health under the Help section to see platform-side degradation signals. You'll typically see: Increased pull latency as traffic shifts to a more distant replica Resource Health flagging known issues in the affected region Replication status indicating which replicas are online After the region recovers, the per-registry health evaluation marks it healthy again and the global endpoint resumes routing — automatic, no cooldown, no customer action. Note that health is evaluated per registry, not per region: if a degradation affects only a subset of registries in a region, only those registries are rerouted, and other registries in the same region continue to be served locally with no unnecessary latency penalty. Not triggered by throttling. Health-aware failover is DNS-based and responds to regional ACR service health and Azure infrastructure health. It does not reroute traffic based on HTTP 429 (throttling) responses. If a geo-replica is throttling your requests but the region's infrastructure is healthy, the global endpoint continues routing you to that geo-replica. To manage throttling, use regional endpoints to spread workloads across multiple geo-replicas for better capacity distribution. Note on long-running pushes during a failover. A multi-layer push that spans a failover boundary can land layers and the manifest on different replicas — exactly the failure mode that DNS bouncing produces during a single push. ACR is actively tightening health-aware failover behavior to minimize cross-replica scatter during these scenarios, and the recommendation today remains: pin pushes to a single replica via a regional endpoint when push/pull consistency matters. Common Questions Q1. Performance impact during initial replica creation on a live registry Because ACR is multi-region, multi-write, the existing replica continues serving pull and push traffic throughout the period when a new replica is being seeded. Replication is asynchronous and content propagates in the background; the time to populate a new geo-replica scales with the size of the registry — the cumulative number and total size of images already in the registry — not with any single image. The docs do not publish a quantified degradation percentage or a throttling window for this period, and they do not promise zero performance impact — the safe operating assumption for a live production registry is that existing replicas continue serving traffic normally, with the new replica catching up in the background. Q2. Restricted/updating state during initial sync There is no "restricted" state for the registry during normal replica creation. Writes, control-plane operations, and pushes/pulls against existing replicas continue normally. The only time configuration changes are unavailable is during a home region outage — see the relevant FAQ item later on for the full data-plane-versus-control-plane breakdown. Q3. Cooldown periods and non-straightforward failback scenarios There is no cooldown before failback, manual or automatic. Re-enabling a replica's participation in global endpoint routing takes effect immediately on ACR's side. Health-aware failover returns traffic to a region as soon as its per-registry health evaluation passes again. The failback case that is not seamless: if a recently pushed image has not yet replicated to the failover region, a pull from that region may not find the image until replication catches up. This is a function of eventual consistency, not failback timing — and it's part of a broader class of issues we cover in Q4. Q4. Common pull and push failure modes during the eventual-consistency window DNS bouncing during a single push is one well-known problem, but it isn't the only one. The eventual-consistency window between geo-replicas surfaces in several recurring failure modes worth knowing about: Push-then-immediate-pull-cross-region. Pushing myapp:v1 to one region and immediately pulling it from a different region can fail with manifest unknown until replication catches up. This shows up most painfully in CI/CD pipelines where one CI runner pushes an image and thousands of pods across other regions all try to pull from their local geo-replicas at the same time. Today, customers work around this with indeterminate sleeps before scheduling expensive compute, or with retry logic, or by waiting on a replication-complete signal — none of which is a clean planning story. Tag overwrite races. Pushing myapp:v1 , then re-pushing myapp:v1 shortly after with a fix (same tag, different digest), can leave different replicas resolving the same tag to different digests during the eventual-consistency window. Delete propagation. Deleting a tag or repository in one region takes some time to propagate to other replicas. Pulls from regions where the delete hasn't yet propagated can return the supposedly-deleted content. Mid-push failover scatter. A multi-layer push that spans a health-aware failover boundary or a DNS bouncing event can land layers on one replica and the manifest on another, surfacing as manifest validation errors or blob unknown on subsequent pulls. What ACR is doing about this. We're working on bounded staleness consistency for pushed images across all geo-replicas worldwide, which addresses these four failure modes directly. This will be covered in an upcoming blog post. If you're hitting eventual-consistency brittleness today and want to talk through your scenario, reach out to us on the Azure Container Registry GitHub repository — we want the customer signal to land in the design. Mitigations available today: Pin pushes to a single replica via a regional endpoint. Every sub-request in the push — login, blob uploads, manifest upload — goes to the same replica, eliminating the DNS bouncing and mid-push scatter classes entirely. Use a short-lived client-side DNS cache like dnsmasq scoped to the duration of a single push, only when you're not using regional endpoints. Do not run a long-lived DNS cache for the global endpoint — it interferes with --global-endpoint-routing false and with health-aware failover routing. Build retry logic into pulls that immediately follow a cross-region push. Either retry with backoff or check replication status with ACR webhooks before pulling. ACR can detect and notify you when an image or tag is available for pull in a geo-replica (say geo-replica B), after it has been pushed to another geo-replica (geo-replica A) and background replication has succeeded to geo-replica B. Design publish steps to be idempotent so retries triggered by mid-push failover are safe. Q5. Auth behavior across endpoint switches For safety, treat each global endpoint and each regional endpoint as its own authenticated surface. All registry APIs except the actual blob downloads (auth, manifests, tag resolution, referrers) flow through whichever endpoint you've chosen. If you switch from the global endpoint to a regional endpoint, or from one regional endpoint to another, re-authenticate. That means az acr login , fresh SDK auth, or — for AKS — letting the Kubernetes ACR credential provider handle re-auth, which it does automatically when the endpoint changes. Q6. Throttling under failover and pinning Throttling limits on registry API operations are per-replica, not per-registry. This has two operational implications: During health-aware failover, traffic that was spread across replicas can shift heavily onto whichever replicas remain in the global endpoint's routing pool. Capacity plan to spread traffic across two or three healthy replicas during a failover scenario rather than concentrating onto one — the global endpoint's routing already does this for you when multiple healthy replicas exist, but registries with only two regions configured can hit per-replica limits more easily during a failover. To mitigate, use regional endpoints to spread workloads across multiple geo-replicas and plan per-replica capacity. When pinning via regional endpoints (Step 2a), you concentrate traffic on whichever replica you've pinned to. If you've pinned all your AKS clusters to a single regional endpoint, you may hit that replica's per-region throttling limits at peak. Mitigations: pin different workloads to different regional endpoints across multiple regions for better topology mapping and capacity distribution, or use the global endpoint (Step 2b) for workloads where you don't need explicit pinning so ACR's routing can spread load. We're also working on improving the throttling metrics surfaced during health-aware failover events. Note: Health-aware failover does not reroute traffic based on HTTP 429 (throttling). If you're experiencing throttling but the region's infrastructure is healthy, the global endpoint continues routing you there. Use regional endpoints to explicitly spread load across replicas for capacity planning. Q7. Home region outage scope Geo-replication provides high availability for the data plane. During a home region outage, the control plane is unavailable, which means you can't create or delete replicas, modify network rules, or change replication settings until the home region recovers. ACR Tasks are also bound to the home region and don't run while it's unavailable. The data plane keeps working: Global endpoint continues routing pulls and pushes to healthy replicas. Regional endpoints continue working — you talk directly to specific replicas, and your client-side logic decides which region to use. Authentication, manifests, blob downloads, webhooks continue functioning through any healthy replica. The home region of a registry is fixed at creation and cannot be changed afterward. Microsoft's registry relocation guidance describes a redeployment procedure — creating a new registry in a different region — not an in-place change to an existing registry's home region. Note: If your registry uses a customer-managed key, review the key vault failover and redundancy guidance for maximum resilience. Key vault availability directly affects the registry's ability to encrypt and decrypt data. Q8. Webhooks during failover Webhooks fire from the replica that received the push. Because ACR also replicates content to other geo-replicas, webhooks fire from each geo-replica as the image syncs to it — so a single push results in webhook events from the receiving replica plus an event from each replica as replication completes. During a failover where pushes are routed to a different region, webhooks from those pushes fire from the new region; once the original region recovers and replication catches up, webhook events fire from there too. Webhook consumers should be designed to handle multiple events per pushed image and deduplicate as needed. Q9. Private endpoints with regional endpoints and dedicated data endpoints When a private endpoint is created against a registry, the private endpoint covers all of the registry's endpoint surfaces — the global endpoint, every regional endpoint (if regional endpoints are enabled), and every regional dedicated data endpoint. A single private endpoint in one VNet can reach the global endpoint (which routes you to a suitable replica), any regional endpoint in the same or a different region, and any region's dedicated data endpoint for blob downloads. The trade-off is private IP allocation: each endpoint surface consumes IPs in the VNet. With many replicas plus regional endpoints plus dedicated data endpoints all enabled, private endpoint creation can fail if the VNet runs out of available private IPs. IP address consumption per feature: Configuration IPs consumed per VNet Initial private endpoint (global endpoint + home region dedicated data endpoint) 2 Each geo-replication region added +1 (regional dedicated data endpoint) Regional endpoints enabled +1 per geo-replica Example: A registry with 3 geo-replicas and regional endpoints enabled consumes 7 private IPs per VNet: 1 (global) + 3 (data) + 3 (regional). Without regional endpoints, the same registry requires 4 private IPs: 1 (global) + 3 (data). Subnet sizing: Use at minimum a /27 (32 addresses) subnet for PE subnets on geo-replicated registries, and /24 where possible. To check how many private IPs are already consumed on a subnet: az network vnet subnet show \ --name <subnet-name> \ --vnet-name <vnet-name> \ --resource-group <resource-group> \ --query "{addressPrefix:addressPrefix, usedIPs:length(ipConfigurations || \`[]\`)}" \ --output table See the ACR private endpoints documentation for the full IP-allocation math and sizing guidance. Q10. Geo-replica creation stuck for private endpoint-enabled registries When creating a geo-replica for a registry that has private endpoints configured, the replica provisioning can get stuck in a Creating state if the identity performing the operation doesn't have sufficient permissions to create private endpoint networking resources. Solution: Manually delete the geo-replica that got stuck in the provisioning state. Ensure the identity has the permission Microsoft.Network/privateEndpoints/privateLinkServiceProxies/write before creating the geo-replica again. Also verify that every PE subnet connected to the registry has free IP capacity — if any PE subnet across any connected VNet does not have enough free IPs, the replication provisioning fails and rolls back. The replica appears briefly in a Creating state and then is removed. The resulting error does not identify which subnet or VNet is exhausted. Q11. Metrics, logs, and alerts for the three phases We map each phase to the signals available in the Monitoring Guidance section below. The headline: Resource Health (in the Azure portal) and az acr replication list give you the platform-side signals; Azure Monitor platform metrics are collected automatically, and resource logs require Diagnostic Settings to be enabled on the customer side. Behavior summary Scenario Automatic? Customer Action Required Notes Registry in a region degrades Yes None Health-aware failover; per-registry; minutes-scale; global endpoint operations only Region recovers after a degradation event Yes None No cooldown Pin AKS clusters to co-located replicas No Use regional endpoint URLs in deployment manifests (Step 2a) Coexists with global endpoint No pinning needed for most workloads Yes None — keep using myregistry.azurecr.io (Step 2b) Global endpoint plus health-aware failover Push/pull from the same replica (consistency) No Use a regional endpoint for both push and pull Eliminates DNS bouncing and mid-push scatter Capacity planning per region No Spread workloads across multiple regional endpoints Per-replica throttling; avoid concentrating on one replica DR rehearsal: take a replica out of global routing No az acr replication update --global-endpoint-routing false Data continues syncing both directions; costs continue accruing Re-enable replica participation in global routing No az acr replication update --global-endpoint-routing true No cooldown; replica is immediately ready Switch a workload between endpoints No Re-auth ( az acr login , SDK auth, or Kubernetes ACR credential provider) Each endpoint is its own authenticated surface Initial replica seeding on a live registry N/A None Existing replica continues serving traffic; seeding time scales with registry size Long-running push during a failover No Retry; design publishes to be idempotent Pin via regional endpoint to avoid mid-push scatter; ACR is tightening this behavior Pull of a recently pushed image from a different region No Wait for replication, retry with backoff, or check replication status Eventual consistency; bounded staleness consistency in development Home region outage Data plane: yes; control plane: no Use global or regional endpoints for data plane operations Control plane (replica config, network rules) requires home region DNS and Client-Side Considerations DNS bouncing during a single push is the most common geo-replication push problem in customer threads, and it warrants a section of its own. The failure mode. A docker push is a sequence of HTTP requests: blob uploads for each layer, then a manifest upload that references those layers by digest. If the Linux DNS resolver on the client doesn't cache myregistry.azurecr.io consistently for the duration of the push, individual sub-requests can resolve to different replicas. Because replication is eventually consistent, the manifest can land on a replica that doesn't yet have the layers it references, and the manifest validation fails. The two mitigations: Regional endpoints pin the push to a single replica end-to-end. Every sub-request — login, blob uploads, manifest upload — goes to the same replica. This is the cleanest fix and the one we recommend for any pipeline where push/pull consistency matters. A short-lived client-side DNS cache like dnsmasq scoped to the duration of a single push. For Linux VMs in Azure, follow the DNS name resolution options guidance. The pin should last the push and no longer. For other clients performing pushes, you can customize your stack's DNS resolver to have a similar short-lived DNS cache to pin the global endpoint's resolved DNS for only the duration of an image push operation. A note on long-lived DNS caching for the global endpoint. Don't run a long-lived DNS cache for myregistry.azurecr.io . ACR purges its own DNS records on the server side when a replica is taken out of global routing (Step 3) and during health-aware failover; a long-lived client-side cache will keep clients pointed at the old region after our purge, which makes both the manual disable mechanism and health-aware failover look broken from the client's perspective. Retry behavior: In-flight pushes during a failover may fail. Design publish steps to be idempotent so retries are safe. Pipelines that push in one region and immediately pull from a different region should retry with backoff or check replication status — eventual consistency means the pull may race ahead of replication. ACR is working on bounded staleness consistency that addresses this directly by enabling proxying (on ACR infrastructure) an image pull request from one geo-replica (if it does not have the image) to another geo-replica that has the image; see the relevant FAQ item. Note: Specific retry counts, back-off intervals, and push timeout values are application-layer decisions. The platform behavior is documented; the retry policy belongs to your client. Monitoring Guidance We map the three phases to the signals available from each source. Where a signal requires customer-side configuration, we flag it. Phase A: Initial replication (after creating a new replica) az acr replication list and az acr replication show — confirm the new replica reaches provisioningState: Succeeded and status: online , and view per-replica status. Azure Monitor platform metrics — push count, pull count, and other registry metrics are collected automatically and visible in the Azure portal under Metrics. No customer configuration is needed to view platform metrics. To export metrics or enable resource logs (detailed operation logs), configure Diagnostic Settings on the registry. Phase B: Failover (planned via replica disable, or automatic via health-aware failover) Per-replica regionEndpointEnabled state via az acr replication list — confirms whether a manual disable took effect, i.e. which replicas are currently eligible for global endpoint routing. Note: this flag reflects the manual configuration for configuring a geo-replica's global endpoint routing eligibility; it does not indicate whether health-aware failover has actively rerouted traffic away from a replica. Resource Health for the registry (in the Azure portal under Help > Resource health) — surfaces platform-side degradation signals during incidents. ACR does not yet expose a definitive "this region is currently serving your traffic" signal; Resource Health and client-side latency changes are the best available indicators. Pull latency from clients — increased latency from a more distant replica is the client-observable signal that traffic has rerouted. Azure Monitor platform metrics — visible per-region in the Azure portal Metrics blade. To export metrics or query them programmatically, enable Diagnostic Settings. Phase C: Failback (replica returns to global routing) az acr replication list — confirms regionEndpointEnabled: True (manual) or online status across all replicas (automatic). Pull latency normalizing as clients reach the recovered replica again. Resource Health clearing for the registry (visible in the Azure portal). Note: The health-aware failover blog calls out ongoing work to surface richer signals — including notifications for when routing changes and which region is currently serving your traffic. The signals listed above are what's available today. Pricing Considerations Storage billing vs. storage quota: Storage is billed per geo-replica — a 1 GiB image replicated to 5 geo-replicas is charged as 5 GiB of storage (1 GiB × 5 geo-replicas). However, storage quota (the tier's maximum storage limit) counts the image only once — the same 1 GiB image counts as 1 GiB toward your tier's maximum, not 5 GiB. Data transfer: Geo-replication can reduce costs by enabling in-region image pushes and pulls, which avoids cross-region data transfer charges during these push or pull operations. However, cross-region data transfer charges still apply when ACR replicates pushed content to other geo-replicas as part of eventual consistency. Disabled replicas still cost: When you take a replica out of global routing with --global-endpoint-routing false , storage and per-replica costs continue accruing because data continues syncing bidirectionally. For more information, see ACR pricing. Cleanup Run these commands to undo the walkthrough setup. Order matters: disable regional endpoints before deleting replicas, since regional endpoint URLs depend on which replicas exist. # Disable regional endpoints if you enabled them in Step 2a az acr update -n myregistry -g myrg --regional-endpoints disabled # Re-enable any replicas you disabled in Step 3 (no-op if already enabled) az acr replication update --registry myregistry --name westus \ --global-endpoint-routing true # Delete the West US replica created in Step 1 az acr replication delete --registry myregistry --name westus # Confirm only the home region replica remains az acr replication list --registry myregistry --output table Note: Replica deletion is a control-plane operation that requires the home region to be available. During a home region outage, replica configuration cannot be modified. Summary Table Question Answer When should I use regional endpoints vs the global endpoint? Use regional endpoints (Step 2a) for workloads that need affinity, predictable routing, push/pull consistency, troubleshooting, or client-side failover. Use the global endpoint (Step 2b) for everything else and let health-aware failover handle routing. What should I enable for secure, resilient layer downloads? Enable dedicated data endpoints. They scope firewall rules tightly to your registry and replace wildcard storage DNS with predictable per-region FQDNs. How do I avoid DNS-bouncing manifest validation failures on push? Pin pushes to a single replica via a regional endpoint. A short-lived client-side dnsmasq for the push duration is also fine if you're not using regional endpoints. Should I run a long-lived DNS cache for the global endpoint? No. ACR purges DNS server-side on disable and during failover; client-side caching works against that. Do I need to re-auth when switching endpoints? Yes. Each global or regional endpoint is its own authenticated surface. az acr login , SDK auth, or the Kubernetes ACR credential provider handles the re-auth. What happens during a home region outage? Data plane keeps working through any replica via the global endpoint or regional endpoints. Control plane operations (replica configuration, network rules) are unavailable until the home region recovers. The home region is fixed at registry creation. What's ACR doing about eventual-consistency pain? Bounded staleness consistency for cross-replica pushed images is in development and will be covered in an upcoming blog post. Reach out via GitHub if you want to share your scenario. For the full automation matrix — what's automatic, what requires customer action, and what to expect for each scenario — see the behavior summary above. If you have further questions about ACR geo-replication routing, pinning, capacity planning, eventual consistency, or failover behavior, reach out to us on the Azure Container Registry GitHub repository or file feedback through the Azure portal.Regional Endpoints for Azure Container Registry Geo-Replication — Now in Public Preview
By Johnson Shi, Zoey (Zhuyu) Li, Huangli Wu What's new Regional endpoints for geo-replicated Azure Container Registries are now in public preview. See the feature's official MS Learn documentation. If you've been following since the private preview announcement, here's what changed: No feature flag registration. No subscription enrollment so all Azure subscriptions and customers can now use this feature. No CLI extension. Regional endpoints commands are built into Azure CLI 2.86.0+ natively. If you installed the private preview acrregionalendpoint extension, uninstall it to avoid conflicts. Native CLI and portal support. With Azure CLI 2.86.0+, enable regional endpoints for all geo-replicas of a registry with az acr create --regional-endpoints enabled or az acr update --regional-endpoints enabled . The Azure portal also supports configuring regional endpoints natively. CLI flag rename for configuring a geo-replica's global endpoint routing (an existing separate feature). The existing flag --region-endpoint-enabled (on az acr replication create/update ) has been renamed to --global-endpoint-routing . Key clarifications: "--global-endpoint-routing" (formerly "--region-endpoint-enabled" on "az acr replication create / az acr replication update") — controls whether a specific geo-replica participates in global endpoint routing. This is an existing feature that is different from the new registry-level "--regional-endpoints" feature being discussed in this post. "--regional-endpoints" (on az "acr create / az acr update") — enables or disables the regional endpoints feature at the registry level for all geo-replicas. This is the feature discussed in this post. See the endpoint reference for the full breakdown of the various registry endpoints (global endpoints, regional endpoints, and data endpoints). Regional endpoints are available on Premium SKU registries in all Azure public cloud regions. What are regional endpoints? Regional endpoints give you dedicated, per-region login server URLs for each geo-replica with the following URL pattern: myregistry.eastus.geo.azurecr.io myregistry.westeurope.geo.azurecr.io Regional endpoints coexist with the registry's global endpoint ( myregistry.azurecr.io ) — enabling regional endpoints doesn't disable a registry's global endpoint that is backed by Azure-managed routing. You can choose per workload: You can use the global endpoint with automatic Azure-managed routing with health-aware failover, where Azure will route your requests to the geo-replica with the best network performance profile to the client. You can use a regional endpoint when you need explicit control or routing to a specific geo-replica. Other resources: For the full background on why regional endpoints exist and the problems they solve, see the private preview blog post. For the complete operational deep dive — health-aware failover, throttling considerations, storage quota and pricing, eventual consistency, home region outage behavior, DNS propagation, private endpoint interaction, capacity planning, and monitoring guidance — see How ACR geo-replication handles failover, failback, and traffic redirection. For the behind-the-scenes engineering implementation — architectural overview and the engineering system design of the feature — see Determinism over magic: the engineering design behind Azure Container Registry Regional Endpoints. Getting started Enable regional endpoints on an existing registry: az acr update -n myregistry -g myrg --regional-endpoints enabled View all registry endpoint URLs, including the registry global endpoint, geo-replica regional endpoints, and data endpoints: az acr show-endpoints --name myregistry --resource-group myrg Using regional endpoints Authenticate to a specific regional endpoint: az acr login --name myregistry --endpoint eastus Push to a specific geo-replica. Images and tags pushed to a geo-replica via regional endpoints still propagate to all other geo-replicas under eventual consistency. docker tag myapp:v1 myregistry.eastus.geo.azurecr.io/myapp:v1 docker push myregistry.eastus.geo.azurecr.io/myapp:v1 Pull an image: docker pull myregistry.eastus.geo.azurecr.io/myapp:v1 You can specify regional endpoints directly in Kubernetes deployment manifests if you need to pin workloads to specific regions. This ensures clusters in specific regions always pull from their colocated replica, providing predictable routing and reduced latency. By using different regional endpoints in each cluster's manifests, you can choose to guarantee that each cluster pulls from its local replica instead of relying on Azure-managed routing. East US cluster deployment: apiVersion: apps/v1 kind: Deployment metadata: name: myapp-eastus spec: template: spec: containers: - name: myapp image: myregistry.eastus.geo.azurecr.io/myapp:v1 West Europe cluster deployment: apiVersion: apps/v1 kind: Deployment metadata: name: myapp-westeurope spec: template: spec: containers: - name: myapp image: myregistry.westeurope.geo.azurecr.io/myapp:v1 When to use regional endpoints Scenario What to do Most workloads Keep using the global endpoint ( myregistry.azurecr.io ). Health-aware failover handles routing automatically. Pin AKS clusters to co-located replicas Use regional endpoint URLs in deployment manifests. CI/CD push-then-pull consistency Pin pushes to a regional endpoint to avoid eventual-consistency races. Client-side failover Switch between regional endpoints based on your own health checks. Capacity planning Spread workloads across multiple regional endpoints to avoid per-replica throttling. Troubleshooting Target a specific geo-replica to reproduce or isolate an issue. What changed from private preview Private preview Public preview Feature flag registration required ( az feature register ) No registration needed Subscription private preview enrollment and propagation wait Immediately available to all Azure subscriptions for all Premium SKU registries in all Azure public cloud regions. Separate CLI extension ( acrregionalendpoint ) Built into Azure CLI 2.86.0+ natively No registry-level CLI flag az acr update --regional-endpoints enabled enables regional endpoints for all geo-replicas --region-endpoint-enabled flag for controlling a geo-replica's global endpoint routing via az acr replication update Flag for controlling a geo-replica's global endpoint routing renamed to --global-endpoint-routing No portal support Native Azure portal support for enabling regional endpoints for new registries (during creation) and for existing registries Private preview docs in Azure/acr Full documentation on MS Learn Enabling regional endpoints in the Azure portal You can enable regional endpoints directly from the Azure portal for both new registries (during creation), as well as existing registries: If you were in the private preview 1. Uninstall the CLI extension. The private preview CLI extension conflicts with the built-in commands in Azure CLI 2.86.0+. Remove it: az extension remove --name acrregionalendpoint Verify it's gone: az extension list --query "[?name=='acrregionalendpoint']" -o table 2. Ensure you're running Azure CLI 2.86.0 or later. Regional endpoints commands are available natively starting in Azure CLI 2.86.0. Check your version: az version 3. Update scripts that use --region-endpoint-enabled for controlling global endpoint routing for a geo-replica. The old flag name for controlling a geo-replica's global endpoint routing configuration is deprecated and will be removed in Azure CLI 2.87.0 (June 2026). Update to --global-endpoint-routing : # Old (deprecated) az acr replication update --registry myregistry --name westus \ --region-endpoint-enabled false # New az acr replication update --registry myregistry --name westus \ --global-endpoint-routing false Why the rename? The old flag name --region-endpoint-enabled was confusing — it sounded like it controlled the regional endpoints feature, but it actually controlled whether a geo-replica participates in global endpoint routing. The new name --global-endpoint-routing says exactly what it does. For a full breakdown of all three CLI flags and how they relate, see the endpoint reference. Learn more Full documentation: Geo-replication in Azure Container Registry — Regional endpoints — prerequisites, CLI commands, network considerations, private endpoint integration, and troubleshooting. Operational deep dive: How ACR geo-replication handles failover, failback, and traffic redirection — health-aware failover, throttling, eventual consistency, DNS considerations, monitoring, pricing, and a full walkthrough. Behind-the-scenes engineering implementation: Determinism over magic: the engineering design behind Azure Container Registry Regional Endpoints — architectural details and the engineering system design behind the feature. Endpoint reference: Azure Container Registry endpoint reference — all endpoint types, URL formats, and CLI flags in one place. Private endpoints: Connect privately to a registry using private endpoints — IP allocation math, subnet sizing, and NIC queries for registries with regional endpoints. Firewall rules: Configure firewall access rules — which FQDNs to allow for regional endpoints. Feedback We'd love to hear how you're using regional endpoints and what we can improve. Reach out via: Azure Container Registry GitHub repository — issues, feature requests, and discussion Azure portal feedback — use the feedback button in the Azure portal on your registry's page Regional endpoints are on the path to GA. Your feedback directly shapes the feature's direction.Azure Functions MCP Extension: What's New at Build 2026
The Azure Functions MCP extension has had a breakout year! Since its initial preview, the extension has grown from a single trigger type into a full-featured platform for building remote MCP servers: with tool, resource, and prompt triggers across multiple languages, MCP Apps for interactive UIs, built-in MCP authentication, and feature enhancements. Here's what's new and what it means for developers building MCP servers on Azure Functions. The full MCP primitive set: Tools, resources, and prompts When the MCP extension first shipped, it supported tool triggers. Declare a function as an MCP tool, and any MCP client can discover and call it. That was the starting point. Since then, we've shipped the remaining MCP primitives: Resource triggers: expose a function as an MCP resource. Prompt triggers: expose a function as an MCP prompt, letting clients request structured prompt templates from your server. Like tool triggers, resource and prompt triggers are supported in multiple languages including .NET, Java, Python, TypeScript, and JavaScript. MCP Apps: interactive UI from your MCP server MCP Apps let your tools return interactive user interfaces instead of plain text. Combine tool triggers with resource triggers, and your MCP server can serve rich, rendered experiences to MCP-aware clients. The Azure Functions MCP extension supports MCP Apps natively, meaning the same function app that exposes tools and resources can also serve UI components. The launch blog post on the Azure Apps Blog walked through the pattern in detail. For .NET developers, the new fluent builder API (available in the latest NuGet release) makes it easier to compose MCP Apps by chaining tool and resource definitions in a declarative style. MCP authentication The extension supports built-in MCP authentication, implementing the requirements of the MCP auth spec. All samples in the aka.ms/remote-mcp repo enable built-in MCP auth by default with Microsoft Entra ID as the identity provider. Samples have also been updated to demonstrate how to exchange tokens in the On-Behalf-Of (OBO) flow, so your MCP tools can access downstream APIs using the invoking user's identity. Auth configuration in the Azure portal: Preview at Build is a one-click experience in the Azure portal for configuring built-in MCP auth. No more manual app registration creating, configuration and wiring to the server. Just open your server app on the portal and click to enable MCP auth. Try it out! Feature enhancements Beyond the headline primitives and auth, the extension has shipped a steady stream of capabilities the past few months. The following are the notable additions. Structured content Structured content lets you return machine-readable JSON metadata alongside your tool's response via the `structuredContent` field. Clients that support it can programmatically consume the data (e.g. parse fields, render tables, drive downstream logic) rather than just displaying text. Clients that don't support it still get the regular content blocks as a fallback. Rich content types Tools aren't limited to returning plain text. The extension supports the full set of MCP content block types, e.g. `TextContent`, `ImageContent`, `AudioContent`, `ResourceLink`, and `EmbeddedResource`, so your tools can return images, audio clips, references to resources, and inline file content alongside text. Input and output schemas `WithInputSchema` and `WithOutputSchema` give you explicit control over the JSON schemas advertised for your tools. This is especially useful when the auto-generated schema from function parameters doesn't capture the full contract. For example, when your tool accepts a complex nested object or returns a specific shape that clients depend on. Input and output schemas are currently supported in .NET, with support for other languages coming soon. builder.ConfigureMcpTool("SearchDocs") .WithOutputSchema(""" { "type": "object", "properties": { "results": { "type": "array", "items": { "type": "string" } }, "query": { "type": "string" } }, "required": ["results", "query"] } """); Fluent configuration APIs in .NET A set of fluent builder APIs that let you configure MCP primitives declaratively in `Program.cs`: ConfigureMcpTool: add properties, metadata, input/output schemas, or promote a tool to an MCP App ConfigureMcpResource: attach metadata to resources ConfigureMcpPrompt: define prompt arguments and metadata builder.ConfigureMcpTool("sayhello") .WithProperty("name", McpToolPropertyType.String, "Name of the user", required: true) .WithMetadata("ui", new { resourceUri = "ui://index.html" }); What's next Usage of the MCP extension has grown steadily since its preview launch. Tool execution volume has increased 15x over the past several months as more customers move from experimentation to production. As adoption grows, so do the expectations. Developers building production MCP servers are hitting real friction around auth complexity, client configuration, and observability. We're continuing to invest in the extension to address these gaps and help customers be more successful building and hosting MCP servers on Azure Functions. Here's where we're focusing next. Continued auth simplification Auth remains the biggest barrier to getting an MCP server into production. We'll work on: Smoother client setup: making it easier to connect any MCP client to an authenticated Azure Functions MCP server, not just VS Code. Simplified OBO flow: streamlining the experience of On-Behalf-Of authentication so developers can delegate user identity to downstream services with less configuration. Our goal: the secure path should be the easy path. Deeper integration with Microsoft Foundry We'll build tighter integration between Azure Functions MCP servers and Microsoft Foundry. This includes surfacing MCP servers in Foundry Toolbox, a new feature introduced to help Foundry agents discover and consume tools from a single endpoint. Developers will be able to publish an MCP server from Functions and have it available to Foundry agents through Toolbox without manual endpoint configuration. Continued feature enhancement We prioritize based on feedback from the community raised in our GitHub repo. For example, support for streaming output and pagination are top items in our backlog today based on user demand. We also track the MCP spec's evolution closely and will continue shipping support for strategic features as they land. Examples of proposals we're following: MCP Tasks: the Tasks extension (SEP-2663) defines a standard pattern for async, long-running tool calls with durable task handles. This replaces hand-rolled polling patterns and aligns well with Functions' execute-and-return model. Stateless MCP: SEP-2575 proposes removing the mandatory initialization handshake, which is a natural fit for serverless platforms like Azure Functions where fresh instances can handle any request. Have something you'd like us to prioritize? Let us know by filing a request on GitHub. Get started Samples: Samples showcasing most up-to-date features: aka.ms/remote-mcp Documentation: Model Context Protocol for Azure Functions MCP Extension GitHub repo: Azure Functions MCP ExtensionAnyscale on Azure: Powering Enterprise AI at Massive Scale on Azure Kubernetes Service
Somewhere on your AI platform team, an engineer is on call this weekend — not for the model, not for the training run, but for the integration code holding five separate AI processing systems together. Data preparation on one. Training on a second. Evaluation on a third. Serving on a fourth. Observability bolted on across all of it. The glue between them has quietly evolved into a production system of its own, complete with its own failure modes and its own pager. This is what running AI at scale looks like for most enterprises in 2026. To process the full breadth of AI workloads, teams don’t have one platform, but a stack of multiple compute engines — stitched together and monitored around the clock. Training failures become increasingly costly as multi-node GPU clusters remain underutilized and difficult to operate. Inference costs climb in a straight line when they should be bending the other way. And the accelerators underneath, at six figures a year per node, sit at 30–40% utilization. None of this is a model problem. It is a systems problem, and it exposes a divide that is widening across the industry. The AI shift: Moving from API inference calls only to end-to-end AI Most enterprises start an AI journey by calling hosted model APIs. It’s the fastest way to experiment and ship. But as adoption grows, inference costs scale in a straight line while differentiation remains limited. The organizations pulling ahead are doing more than consuming models. They are customizing them with proprietary data, operating them at scale, and owning the infrastructure between their data and their models. Their unit economics improve as they scale. The dividing line isn’t budget. It isn’t ambition. It is a single architectural decision: whether the layer between your data and your models is something you rent in pieces or run as a single system. That unified system for end-to-end AI, almost without exception, is built on one runtime: Ray, an open-source framework widely adopted by AI-natives such as Cursor, Mistral and xAI to act as the engine that powers many of their workloads from multimodal data processing to reinforcement learning. Anyscale on Azure: Build and run end-to-end AI on your Azure subscription Anyscale on Azure brings the distributed compute runtime the AI industry has converged on — Ray— into your Azure tenant as an Azure Native service, that includes purpose-built developer tooling and unified pane for cluster management, built through deep engineering collaboration between Anyscale and Microsoft. Unlike other processing engines which either only support one hardware type (e.g. CPUs) or focus on a single workload (e.g. inference), Ray turns a heterogeneous cluster of CPUs and GPUs into a single Python runtime composing data preparation, distributed training, fine-tuning, reinforcement learning, high-throughput inference, and agentic execution as one program, not five interlocking systems. Anyscale created Ray and stewards the open-source Ray project, now governed by the PyTorch Foundation; the Anyscale Runtime is the production-grade layer that enterprises can utilize on critical paths from day one, bringing managed cluster operations, enterprise-grade support, and the operational reliability needed to run AI and data workloads at scale. On Azure, that runtime executes on your Azure Kubernetes Service (AKS) clusters, inside your subscription, and under Microsoft Entra ID workload identity. Your data, models, and weights never leave your cloud, and consumption is billed through Azure with drawdown against your existing Azure commitment (MACC). Sovereignty isn't a label bolted on after the fact. It is the architectural starting point: customer-owned data and models in the customer-owned tenant and governance boundary. The variable per-token economics of hosted APIs are replaced with compute you govern directly. Your proprietary data becomes a compounding advantage rather than a payload shipped to a third-party endpoint. A single runtime for the full AI lifecycle The cost profile of enterprise AI is largely architectural. Fragmented stacks — separate systems for prep, training, evaluation, and serving — produce a predictable set of failure modes such as Idle GPU time, Integration code and cross-system data movement. The result: production GPU utilization only in the 30–40% range, against accelerators that cost six figures per node per year. On the same fleet, Anyscale customers run those accelerators at 80%+ sustained utilization and report 40–60% lower GPU spend versus static, single-tenant clusters — driven by fractional GPU allocation (down to 0.2 of a device), bin-packing across complementary memory and compute profiles, gang scheduling for distributed training, priority-aware preemption that lets production inference take precedence over ad-hoc training, and spot integration with checkpoint-aware preemption so long-running jobs survive reclamation without lost work. Anyscale on Azure replaces this with a single Ray-powered runtime that spans the lifecycle as one distributed computation graph: Ray Data (distributed preparation) → Ray Train (fault-tolerant training) → Ray Tune (hyperparameter search) → Ray Serve (inference) — under one managed control plane. On top of open-source Ray, the Anyscale Runtime adds fault-tolerant training with checkpoint/restart, optimized scheduling, faster cluster bring-up, inference-aware autoscaling, and per-stage observability. Ray is the unifying layer that, rather than replacing, streamlines distributed processing of the framework stack the AI industry already uses: PyTorch, Hugging Face Transformers, FSDP, DeepSpeed, and Megatron for training, vLLM and SGLang for high-throughput inference with continuous batching, paged attention, and speculative decoding. Ray Train orchestrates the three parallelism patterns modern training requires — data parallel, model parallel, and hybrid 3D parallel (data + tensor + pipeline) — for trillion-parameter models, without requiring teams to write custom distributed code. The architectural payoff is direct: a single Python program defines a graph spanning CPU-heavy preparation and GPU-heavy training. The model produced by Ray Train is served by Ray Serve in the same cluster, against the same storage. The operational, identity, and observability surface is unified instead of fragmented. What enterprises deploy with Anyscale on Azure There are five workloads that power the development of modern AI systems, spanning data processing, training, inference, and simulation. But in most environments, each depends on separate engines, frameworks, and orchestration layers. The resulting fragmentation drives up infrastructure spend, latency, and engineering complexity. This makes a single Ray-based runtime under Anyscale’s managed control plane the operationally rational choice. Anyscale on Azure provides a complete platform to build and deploy AI applications using the same APIs as open-source Ray. While the data plane runs inside the customer’s AKS cluster, the managed control plane provides a unified interface for development, debugging, and cluster operations. AI in your trust boundary by design: the architecture Anyscale on Azure is an Azure Native product — discoverable via the Azure portal and provisioned through Azure Resource Manager with every resource tagged, scoped, and policy‑bound like any other in your subscription. Anyscale on Azure is a split-plane deployment: Control plane (managed by Anyscale) — scheduling, jobs, services, workspaces, and observability. Data plane (your Azure subscription) — Ray clusters run on your AKS, in your VNet, on your storage (Azure Blob / ADLS Gen2 via BlobFuse2). The trust boundary is what matters — more than any individual data plane feature — for regulated workloads (financial services, healthcare, public sector) and any enterprise where proprietary data is the differentiation. The execution model: Workloads run inside your AKS cluster — your subscription, your VNet. Model weights, training data, KV caches, checkpoints, and inference traffic never leave the boundary. Provisioning is ARM-native — resources tag, scope, and inherit Azure Policy like anything else in the subscription. Identity is Microsoft Entra ID end to end — workload identity issues pod credentials; RBAC governs access. No long-lived keys, no parallel secret store. Network controls are yours — Private Link, NSGs, Cilium-based Azure CNI policies, and customer-managed encryption keys via Key Vault. Audit is the Azure Activity Log — the same surface your compliance team already monitors. The Anyscale Operator is the only Anyscale-controlled component in your environment — it runs inside your AKS, communicates with the control plane via egress only, and accepts no inbound access from Anyscale. The result: code and data stay in your Azure subscription. Your existing compliance posture, audit surface, and data residency certifications carry forward — nothing new to attest. Billing rolls through the same Azure invoice with MACC drawdown — no second invoice, no parallel procurement. Production evidence Xoople planetary‑scale satellite imagery on Anyscale on Azure; multimodal AI turns spectral data into operational intelligence. "Anyscale lets our teams focus on models and outcomes rather than infrastructure, dramatically accelerating the path from experimentation to deployment," — Milos Colic, VP of Engineering, Xoople. Wayve trains the next generation of autonomous‑driving foundation models on Anyscale on Azure, running distributed ML and data pipelines across large CPU and GPU fleets. The operational driver is GPU‑capacity aggregation at a scale that no single region or cluster can deliver. Beyond Anyscale on Azure, the same Ray runtime is used in production at Cursor, Physical Intelligence, xAI, Coinbase, Bedrock Robotics, and Runway. Bedrock Robotics scaled compute 85x on Anyscale without linearly increasing costs. Currently with 12M+ weekly downloads (+400% YoY) and 42K+ GitHub stars and now openly governed under the PyTorch Foundation (Linux Foundation), Ray is becoming the de-factor open-source standard and is not a single-vendor runtime. Pricing Pricing is usage‑based and consolidates onto the same Azure invoice as the rest of the customer's subscription, including drawdown against existing Azure commitment (MACC): Azure infrastructure — standard Azure compute and GPU charges for the AKS substrate the workload runs on, scaling directly with actual usage. Anyscale service layer — pay‑as‑you‑go through Azure service meters with no upfront commitment, priced by CPU, memory, and GPU type. Where Anyscale on Azure fits Base-model intelligence is converging. Enterprises can buy access to the same frontier models, so the model itself is no longer the moat. What separates the enterprises pulling ahead is the layer underneath: how efficiently they run the full AI lifecycle at scale, how much compounding leverage they extract from their proprietary data, and whether they own the runtime that ties it all together. Anyscale on Azure is the Azure Native runtime layer for that posture — bringing the open-source distributed compute standard the AI industry has converged on into the same Azure governance, identity, and procurement model as the rest of the tenant. The shape of enterprise AI is settling. The teams pulling ahead are not the ones renting the most intelligence through APIs — they are the ones building and operating AI systems inside their own cloud, on their own data, under their own governance, and scaling those systems on the open distributed runtime the industry has already converged on. Anyscale on Azure is that runtime, delivered as an Azure Native product: Ray, productionized — the open‑source distributed compute standard for AI, hardened with the Anyscale Runtime, a managed control plane, and observability designed for foundation‑model‑scale workloads. One runtime, the full AI lifecycle — data preparation, training, fine‑tuning, reinforcement learning, inference, and agentic workloads in a single Python program, on a single substrate, with no cross‑system glue. Inside your Azure tenant, on the AKS you already run — customer‑owned data, customer‑owned models, customer‑owned governance. Entra identity, Azure RBAC, Private Link, Activity Log audit, and customer‑managed keys end to end. One Azure invoice — usage‑based pricing through the Marketplace with MACC drawdown; no parallel procurement, no second vendor contract. If your team is wrestling with GPU utilization, fragmented data‑to‑serving stacks, training jobs that exceed any single region's capacity, or hosted‑API costs that scale faster than your usage — this is the runtime built for that problem. Try it now Provision your first Anyscale Cloud by navigating to the Azure portal. Click on "Create" to begin creating the Anyscale cloud resource and link the necessary Azure resources. your Anyscale Cloud directly from Azure Portal. e. Explore the quickstart guides and documentation on Microsoft Learn to get started. For architectural deep‑dives, capacity planning, or a hands‑on workshop with the Anyscale on Azure solution architects, reach out through your Microsoft account team. Deepen your expertise and deep dive on best practices in the upcoming virtual webinar. Register here. The infrastructure for the next decade of enterprise AI is here. Build on it. Links and Resources Press Release: Anyscale Launches on Microsoft Azure as a Native Integration for Enterprises Announcing Anyscale on Azure public preview: Powered by Ray on AKS Youtube Video: Anyscale on Azure: Scale Python AI workloads with managed Ray on AKS Azure on Anyscale overview Architecture Create an Anyscale Cloud in Azure Portal Pricing Support model Terms and Conditions Frequently asked questionsIntroducing On-demand Sandboxes for Azure Durable Task Scheduler (Private Preview)
Maybe it needs a native toolchain. Maybe it runs untrusted customer or LLM-generated code. Maybe it needs Python from a .NET orchestrator, or bursty compute that should scale to zero when the work is done. Today, we're thrilled to announce On-demand Sandboxes for Azure Durable Task Scheduler, now available in private preview. On-demand Sandboxes lets you move those individual workflow steps to managed, isolated compute while your orchestrator stays exactly where it is. Tell DTS which steps should run in isolation, provide a container image with the step code, and DTS handles provisioning, scaling, and teardown. No infrastructure to manage, no idle costs, no orchestrator changes. Sign up for On-demand Sandboxes Private Preview Today → Availability: On-demand Sandboxes targets the standalone Durable Task SDKs used outside the Azure Functions host — for apps running on Azure Container Apps, Azure Kubernetes Service, App Service, or anywhere else you self-host. The private preview supports the .NET and Python Durable Task SDKs, with additional language SDKs and Azure Functions support coming soon. What is Azure Durable Task Scheduler? The Durable Task Scheduler is a fully managed backend for durable execution on Azure. It can serve as the backend for a Durable Function App using the Durable Functions extension, or as the backend for an app leveraging the Durable Task SDKs in other compute environments, such as Azure Container Apps, Azure Kubernetes Service, or Azure App Service. For a deeper introduction, see the Durable Task Scheduler overview or the full Durable Task documentation. Why On-demand Sandboxes? Most activities belong in-process. They're fast, simple, and co-located with your orchestrator. But sometimes you hit a step that doesn't fit: it needs a native binary, a different language runtime, per-invocation isolation, or bursty compute you don't want to keep warm. On-demand Sandboxes gives you a way to handle those exceptions without spinning up dedicated infrastructure or managing scaling policies in Azure Kubernetes Service or Azure Container Apps. Activity-level granularity. Move individual steps to managed compute, not your whole app. Per-activity or per-invocation isolation. Each execution runs in a clean, microVM-backed sandbox. Ideal for untrusted code, customer plugins, or LLM-generated logic. Cross-runtime flexibility. Run a Python inference step from a .NET orchestrator. No compromise on either side. Scale-to-zero. Pay for CPU and memory per second of execution, not infrastructure that waits. No orchestrator changes. Your orchestration code and hosting model don't change at all. Here are a few scenarios where On-demand Sandboxes shines: Native toolchains. Package ffmpeg, LibreOffice, or Pandoc in a container without dragging them into your main app. CPU-heavy preprocessing. OCR, layout extraction, or image processing can scale independently of the rest of your workflow. Cross-runtime workflows. A .NET orchestrator dispatches a Python inference step. No compromises. Sandboxed code execution. Run customer plugins or LLM-generated code with a clean boundary on every invocation. Multi-tenant isolation. Tenant-specific steps get dedicated boundaries while everything else stays in-process. Bursty event-driven workloads. Steps that spike hard but rarely may not justify always-on infrastructure. Sub-second cold starts mean you get capacity when you need it without paying to keep it warm. How it works On-demand Sandboxes uses a two-part model: a worker profile in your orchestrator app that tells DTS which activities to offload, and a worker image that contains those activity implementations. Your orchestrator still calls activities the same way it always has; the decision to run one activity in a sandbox lives in the profile configuration. 1. Declare a sandbox worker profile In the app that hosts your orchestrator, define a sandbox worker profile. The profile gives DTS the container image, resource shape, concurrency setting, and activity names that should run in a sandbox: using Microsoft.DurableTask.Worker.AzureManaged.Sandbox; [SandboxWorkerProfile("code-executor")] internal sealed class CodeSandboxWorkerProfile : ISandboxWorkerProfile { public void Configure(SandboxOptions options) { options.ContainerImage = Environment.GetEnvironmentVariable("DTS_SANDBOX_IMAGE") ?? throw new InvalidOperationException("DTS_SANDBOX_IMAGE is required."); options.Cpu = "1000m"; options.Memory = "2048Mi"; options.MaxConcurrentActivities = 1; options.AddActivity(TaskNames.ExecuteCode); } } Then enable on-demand sandbox discovery when you configure the Durable Task worker in the main app: workerBuilder.AddTasks(tasks => tasks.AddAllGeneratedTasks()); workerBuilder.UseDurableTaskScheduler(options => { options.EndpointAddress = Environment.GetEnvironmentVariable("DTS_ENDPOINT"); options.TaskHubName = Environment.GetEnvironmentVariable("DTS_TASK_HUB"); options.Credential = credential; }); workerBuilder.EnableSandboxes(); Here's what the profile configuration does: SandboxWorkerProfile: a friendly profile id for this sandbox setup. It groups the activity, image, and resource settings for monitoring and reuse across deployments. ContainerImage: the container image (from your registry) that contains the activity implementations. Cpu / Memory: the resource shape for each worker instance. Sized per your activity's needs. MaxConcurrentActivities: how many activities a single worker instance can process concurrently. AddActivity: the specific activity to offload. Only activities added to a sandbox worker profile execute in DTS-managed isolated compute; everything else stays in-process. The orchestrator call site doesn't change: ExecuteCodeOutput execution = await context.CallActivityAsync<ExecuteCodeOutput>( TaskNames.ExecuteCode, new ExecuteCodeInput(pythonCode, input.CsvData)); ExecuteCode is not registered in the main app's in-process activity list. When the orchestrator calls it, DTS uses the codegen profile to route the work to the sandbox image. 2. Build the worker image The worker image is a container you own. In most apps, this worker lives in a separate project from the orchestrator host so it can have its own entry point, dependencies, and container image. It registers the activity implementations it can run and opts in to managed execution with UseSandboxWorker(): builder.Services.AddDurableTaskWorker(workerBuilder => { workerBuilder.AddTasks(tasks => { tasks.AddActivity<ExecuteCodeActivity>(); }); workerBuilder.UseSandboxWorker(); }); UseSandboxWorker() is the key line. It signals that this worker runs in DTS-managed compute. The sandbox worker does not need to configure the DTS endpoint, task hub, profile id, or credentials; DTS injects the runtime settings when it starts the container. The activity implementations themselves are standard Durable Task activities. There's nothing special about the activity code: it can call a runtime with different dependencies, such as Python and pandas, while running in an isolated container instead of in your main app's process. Package the image like any containerized service, including whatever runtimes and native tools the activity needs. Push it to your container registry (e.g., Azure Container Registry) and reference the image in the worker profile's ContainerImage option. View logs in the DTS dashboard Once your sandbox activities are running, you can view their execution logs directly in the Durable Task Scheduler dashboard. The dashboard shows real-time output from your managed workers, including stdout, stderr, and activity lifecycle events. This gives you full visibility into what's happening inside the sandbox without needing to configure external log sinks or set up your own observability pipeline. Demo Get started On-demand Sandboxes is in private preview. To get access, sign up here. We'll enable the feature on your scheduler and help you get your first sandbox activity running. Once you're in, the workflow is straightforward: declare a sandbox worker profile in your orchestrator app, build and push a worker image, and DTS takes care of the rest. Sign up for On-demand Sandboxes Private Preview Today → Documentation: Durable Task Scheduler overview Samples: Azure-Samples/Durable-Task-Scheduler Pricing: Azure Durable Task Scheduler pricing Questions, feedback, or ideas? Open an issue in the Durable-Task-Scheduler GitHub repo. We'd love to hear from you.
