The Agent that investigates itself
Azure SRE Agent handles tens of thousands of incident investigations each week for internal Microsoft services and external teams running it for their own systems. Last month, one of those incidents was about the agent itself. Our KV cache hit rate alert started firing. Cached token percentage was dropping across the fleet. We didn't open dashboards. We simply asked the agent. It spawned parallel subagents, searched logs, read through its own source code, and produced the analysis. First finding: Claude Haiku at 0% cache hits. The agent checked the input distribution and found that the average call was ~180 tokens, well below Anthropic’s 4,096-token minimum for Haiku prompt caching. Structurally, these requests could never be cached. They were false positives. The real regression was in Claude Opus: cache hit rate fell from ~70% to ~48% over a week. The agent correlated the drop against the deployment history and traced it to a single PR that restructured prompt ordering, breaking the common prefix that caching relies on. It submitted two fixes: one to exclude all uncacheable requests from the alert, and the other to restore prefix stability in the prompt pipeline. That investigation is how we develop now. We rarely start with dashboards or manual log queries. We start by asking the agent. Three months earlier, it could not have done any of this. The breakthrough was not building better playbooks. It was harness engineering: enabling the agent to discover context as the investigation unfolded. This post is about the architecture decisions that made it possible. Where we started In our last post, Context Engineering for Reliable AI Agents: Lessons from Building Azure SRE Agent, we described how moving to a single generalist agent unlocked more complex investigations. The resolution rates were climbing, and for many internal teams, the agent could now autonomously investigate and mitigate roughly 50% of incidents. We were moving in the right direction. But the scores weren't uniform, and when we dug into why, the pattern was uncomfortable. The high-performing scenarios shared a trait: they'd been built with heavy human scaffolding. They relied on custom response plans for specific incident types, hand-built subagents for known failure modes, and pre-written log queries exposed as opaque tools. We weren’t measuring the agent’s reasoning – we were measuring how much engineering had gone into the scenario beforehand. On anything new, the agent had nowhere to start. We found these gaps through manual review. Every week, engineers read through lower-scored investigation threads and pushed fixes: tighten a prompt, fix a tool schema, add a guardrail. Each fix was real. But we could only review fifty threads a week. The agent was handling ten thousand. We were debugging at human speed. The gap between those two numbers was where our blind spots lived. We needed an agent powerful enough to take this toil off us. An agent which could investigate itself. Dogfooding wasn't a philosophy - it was the only way to scale. The Inversion: Three bets The problem we faced was structural - and the KV cache investigation shows it clearly. The cache rate drop was visible in telemetry, but the cause was not. The agent had to correlate telemetry with deployment history, inspect the relevant code, and reason over the diff that broke prefix stability. We kept hitting the same gap in different forms: logs pointing in multiple directions, failure modes in uninstrumented paths, regressions that only made sense at the commit level. Telemetry showed symptoms, but not what actually changed. We'd been building the agent to reason over telemetry. We needed it to reason over the system itself. The instinct when agents fail is to restrict them: pre-write the queries, pre-fetch the context, pre-curate the tools. It feels like control. In practice, it creates a ceiling. The agent can only handle what engineers anticipated in advance. The answer is an agent that can discover what it needs as the investigation unfolds. In the KV cache incident, each step, from metric anomaly to deployment history to a specific diff, followed from what the previous step revealed. It was not a pre-scripted path. Navigating towards the right context with progressive discovery is key to creating deep agents which can handle novel scenarios. Three architectural decisions made this possible – and each one compounded on the last. Bet 1: The Filesystem as the Agent's World Our first bet was to give the agent a filesystem as its workspace instead of a custom API layer. Everything it reasons over – source code, runbooks, query schemas, past investigation notes – is exposed as files. It interacts with that world using read_file, grep, find, and shell. No SearchCodebase API. No RetrieveMemory endpoint. This is an old Unix idea: reduce heterogeneous resources to a single interface. Coding agents already work this way. It turns out the same pattern works for an SRE agent. Frontier models are trained on developer workflows: navigating repositories, grepping logs, patching files, running commands. The filesystem is not an abstraction layered on top of that prior. It matches it. When we materialized the agent’s world as a repo-like workspace, our human "Intent Met" score - whether the agent's investigation addressed the actual root cause as judged by the on-call engineer - rose from 45% to 75% on novel incidents. But interface design is only half the story. The other half is what you put inside it. Code Repositories: the highest-leverage context Teams had prewritten log queries because they did not trust the agent to generate correct ones. That distrust was justified. Models hallucinate table names, guess column schemas, and write queries against the wrong cluster. But the answer was not tighter restriction. It was better grounding. The repo is the schema. Everything else is derived from it. When the agent reads the code that produces the logs, query construction stops being guesswork. It knows the exact exceptions thrown, and the conditions under which each path executes. Stack traces start making sense, and logs become legible. But beyond query grounding, code access unlocked three new capabilities that telemetry alone could not provide: Ground truth over documentation. Docs drift and dashboards show symptoms. The code is what the service actually does. In practice, most investigations only made sense when logs were read alongside implementation. Point-in-time investigation. The agent checks out the exact commit at incident time, not current HEAD, so it can correlate the failure against the actual diffs. That's what cracked the KV cache investigation: a PR broke prefix stability, and the diff was the only place this was visible. Without commit history, you can't distinguish a code regression from external factors. Reasoning even where telemetry is absent. Some code paths are not well instrumented. The agent can still trace logic through source and explain behavior even when logs do not exist. This is especially valuable in novel failure modes – the ones most likely to be missed precisely because no one thought to instrument them. Memory as a filesystem, not a vector store Our first memory system used RAG over past session learnings. It had a circular dependency: a limited agent learned from limited sessions and produced limited knowledge. Garbage in, garbage out. But the deeper problem was retrieval. In SRE Context, embedding similarity is a weak proxy for relevance. “KV cache regression” and “prompt prefix instability” may be distant in embedding space yet still describe the same causal chain. We tried re-ranking, query expansion, and hybrid search. None fixed the core mismatch between semantic similarity and diagnostic relevance. We replaced RAG with structured Markdown files that the agent reads and writes through its standard tool interface. The model names each file semantically: overview.md for a service summary, team.md for ownership and escalation paths, logs.md for cluster access and query patterns, debugging.md for failure modes and prior learnings. Each carry just enough context to orient the agent, with links to deeper files when needed. The key design choice was to let the model navigate memory, not retrieve it through query matching. The agent starts from a structured entry point and follows the evidence toward what matters. RAG assumes you know the right query before you know what you need. File traversal lets relevance emerge as context accumulates. This removed chunking, overlap tuning, and re-ranking entirely. It also proved more accurate, because frontier models are better at following context than embeddings are at guessing relevance. As a side benefit, memory state can be snapshotted periodically. One problem remains unsolved: staleness. When two sessions write conflicting patterns to debugging.md, the model must reconcile them. When a service changes behavior, old entries can become misleading. We rely on timestamps and explicit deprecation notes, but we do not have a systemic solution yet. This is an active area of work, and anyone building memory at scale will run into it. The sandbox as epistemic boundary The filesystem also defines what the agent can see. If something is not in the sandbox, the agent cannot reason about it. We treat that as a feature, not a limitation. Security boundaries and epistemic boundaries are enforced by the same mechanism. Inside that boundary, the agent has full execution: arbitrary bash, python, jq, and package installs through pip or apt. That scope unlocks capabilities we never would have built as custom tools. It opens PRs with gh cli, like the prompt-ordering fix from KV cache incident. It pushes Grafana dashboards, like a cache-hit-rate dashboard we now track by model. It installs domain-specific CLI tools mid-investigation when needed. No bespoke integration required, just a shell. The recurring lesson was simple: a generally capable agent in the right execution environment outperforms a specialized agent with bespoke tooling. Custom tools accumulate maintenance costs. Shell commands compose for free. Bet 2: Context Layering Code access tells the agent what a service does. It does not tell the agent what it can access, which resources its tools are scoped to, or where an investigation should begin. This gap surfaced immediately. Users would ask "which team do you handle incidents for?" and the agent had no answer. Tools alone are not enough. An integration also needs ambient context so the model knows what exists, how it is configured, and when to use it. We fixed this with context hooks: structured context injected at prompt construction time to orient the agent before it takes action. Connectors - what can I access? A manifest of wired systems such as Log Analytics, Outlook, and Grafana, along with their configuration. Repositories - what does this system do? Serialized repo trees, plus files like AGENTS.md, Copilot.md, and CLAUDE.md with team-specific instructions. Knowledge map - what have I learned before? A two-tier memory index with a top-level file linking to deeper scenario-specific files, so the model can drill down only when needed. Azure resource topology - where do things live? A serialized map of relationships across subscriptions, resource groups, and regions, so investigations start in the right scope. Together, these context hooks turn a cold start into an informed one. That matters because a bad early choice does not just waste tokens. It sends the investigation down the wrong trajectory. A capable agent still needs to know what exists, what matters, and where to start. Bet 3: Frugal Context Management Layered context creates a new problem: budget. Serialized repo trees, resource topology, connector manifests, and a memory index fill context fast. Once the agent starts reading source files and logs, complex incidents hit context limits. We needed our context usage to be deliberately frugal. Tool result compression via the filesystem Large tool outputs are expensive because they consume context before the agent has extracted any value from them. In many cases, only a small slice or a derived summary of that output is actually useful. Our framework exposes these results as files to the agent. The agent can then use tools like grep, jq, or python to process them outside the model interface, so that only the final result enters context. The filesystem isn't just a capability abstraction - it's also a budget management primitive. Context Pruning and Auto Compact Long investigations accumulate dead weight. As hypotheses narrow, earlier context becomes noise. We handle this with two compaction strategies. Context Pruning runs mid-session. When context usage crosses a threshold, we trim or drop stale tool calls and outputs - keeping the window focused on what still matters. Auto-Compact kicks in when a session approaches its context limit. The framework summarizes findings and working hypotheses, then resumes from that summary. From the user's perspective, there's no visible limit. Long investigations just work. Parallel subagents The KV cache investigation required reasoning along two independent hypotheses: whether the alert definition was sound, and whether cache behavior had actually regressed. The agent spawned parallel subagents for each task, each operating in its own context window. Once both finished, it merged their conclusions. This pattern generalizes to any task with independent components. It speeds up the search, keeps intermediate work from consuming the main context window, and prevents one hypothesis from biasing another. The Feedback loop These architectural bets have enabled us to close the original scaling gap. Instead of debugging the agent at human speed, we could finally start using it to fix itself. As an example, we were hitting various LLM errors: timeouts, 429s (too many requests), failures in the middle of response streaming, 400s from code bugs that produced malformed payloads. These paper cuts would cause investigations to stall midway and some conversations broke entirely. So, we set up a daily monitoring task for these failures. The agent searches for the last 24 hours of errors, clusters the top hitters, traces each to its root cause in the codebase, and submits a PR. We review it manually before merging. Over two weeks, the errors were reduced by more than 80%. Over the last month, we have successfully used our agent across a wide range of scenarios: Analyzed our user churn rate and built dashboards we now review weekly. Correlated which builds needed the most hotfixes, surfacing flaky areas of the codebase. Ran security analysis and found vulnerabilities in the read path. Helped fill out parts of its own Responsible AI review, with strict human review. Handles customer-reported issues and LiveSite alerts end to end. Whenever it gets stuck, we talk to it and teach it, ask it to update its memory, and it doesn't fail that class of problem again. The title of this post is literal. The agent investigating itself is not a metaphor. It is a real workflow, driven by scheduled tasks, incident triggers, and direct conversations with users. What We Learned We spent months building scaffolding to compensate for what the agent could not do. The breakthrough was removing it. Every prewritten query was a place we told the model not to think. Every curated tool was a decision made on its behalf. Every pre-fetched context was a guess about what would matter before we understood the problem. The inversion was simple but hard to accept: stop pre-computing the answer space. Give the model a structured starting point, a filesystem it knows how to navigate, context hooks that tell it what it can access, and budget management that keeps it sharp through long investigations. The agent that investigates itself is both the proof and the product of this approach. It finds its own bugs, traces them to root causes in its own code, and submits its own fixes. Not because we designed it to. Because we designed it to reason over systems, and it happens to be one. We are still learning. Staleness is unsolved, budget tuning remains largely empirical, and we regularly discover assumptions baked into context that quietly constrain the agent. But we have crossed a new threshold: from an agent that follows your playbook to one that writes the next one. Thanks to visagarwal for co-authoring this post.Announcing Public Preview of Argo CD extension in AKS Azure Portal Experience
We are excited to announce the public preview of Argo CD in the Azure Portal for Azure Kubernetes Service. As GitOps becomes the standard for deploying and operating applications at scale, customers need a way to adopt GitOps with simpler onboarding, secure defaults, and integrated workflows. With Argo CD now available directly in the Portal, teams can enable and manage GitOps without the complexity of manual setup. Bringing GitOps into the AKS experience Argo CD is widely used across Kubernetes environments, but setup often requires manual configuration across identity, networking, and registry integrations. With the Azure Portal experience, customers can: Enable Argo CD directly from the AKS cluster Configure identity, access, ingress, and registry integration in a guided flow Manage and monitor GitOps workflows through Argo CD UI This reduces onboarding friction and helps you reach your first successful GitOps deployment faster. Trusted identity and secure access The Argo CD experience integrates with Microsoft Entra ID to provide a secure, enterprise-ready foundation: Secure authentication using Workload Identity federation to Azure Container Registry (ACR) and Azure DevOps, removing long-lived credentials and hard-coded secrets Single Sign-On (SSO) using existing Azure identities Enterprise-grade hardening and security This preview includes built-in improvements to strengthen security posture: Images built on Azure Linux for reduced CVEs and improved baseline security Optional automatic patch updates to stay current while maintaining control over change management Parity with upstream Argo CD Argo CD in AKS remains aligned with the upstream open-source project, supporting: High availability (HA) configurations for production workloads Hub-and-spoke architectures for multi-cluster GitOps Application and ApplicationSet for scalable deployment across fleets Getting Started We invite you to explore the Argo CD experience in the Azure Portal and share feedback. To get started, go to your AKS cluster in the Azure Portal, navigate to the GitOps experience, and select Enable Argo CD. Follow the guided setup to configure identity, access, ingress, and registry integration with secure defaults. Once enabled, you can monitor your deployment and view application health and sync status from the Argo CD UI linked in the GitOps blade. For customers who prefer automation and scripting, the Argo CD extension is also available via Azure CLI public preview. NOTE: You can choose between Flux and Argo CD as your GitOps solution based on your needs. The Argo CD option is available during the initial GitOps setup experience, while existing Flux users will continue to see their current configuration.
Metrics Filtering and Log Aggregation Now GA for Advanced Container Networking Services
We are thrilled to announce that Advanced Container Networking Services (ACNS) for Azure Kubernetes Service (AKS) now delivers two powerful observability features in General Availability: container network metrics filtering and container network log filtering and aggregation. Together, these capabilities set a new standard for Kubernetes network observability, giving you high-fidelity visibility at dramatically lower cost and noise. These capabilities fundamentally redefine how network observability works at scale while delivering up to 97% cost reduction. Why this is a Milestone? Most Kubernetes observability solutions face a fundamental tension: collect everything and drown in noise and cost, or sample and miss the signals that matter, with new features of Advanced Container Networking Services that tradeoff has been eliminated. With this release, Azure becomes the first cloud provider to deliver on-node metrics filtering and flow log aggregation for Kubernetes networking, capabilities now also contributed to the upstream Hubble project, making them available to the broader open-source community. For AKS customers running Cilium-based clusters, this means: Every flow you care about is captured. Everything else is dropped at the source. Log volume is compressed by up to 45% through aggregation, without losing security verdicts or error context. Costs scale with what you monitor, not with cluster size. What’s been improved in observability? This release introduces two capabilities that work together: container network metrics filtering and container network log filtering and aggregation. Both are available on AKS clusters with the Cilium data plane and give you precise controls to keep observability costs predictable while maintaining the visibility you need. Container Network Metrics Filtering Container network metrics are generated for all pods by default whenever Advanced Container Networking Services is enabled. With metrics filtering, you now control what gets collected at the point of ingestion, on the node, before anything is scraped or transmitted. A single ContainerNetworkMetric CRD per cluster defines which metric types (dns, flow, tcp, drop), namespaces, pod labels, and protocols to ingest. It supports both include and exclude filters, so you can maintain broad collection while carving out specific workloads or namespaces. Anything that doesn't match is dropped on the node. Changes reconcile in a few seconds, with no Cilium agent or Prometheus restarts required. Container Network Log Filtering and Aggregation Unlike metrics, container network logs are not generated automatically. You start capturing network flows only after applying a ContainerNetworkLog CRD that defines exactly which traffic to capture-by namespace, pod, service, protocol, or verdict. Only matching flows are logged, giving you a precise, targeted view rather than a fire hose. This is where Azure's first-to-market innovation comes in. Flow log aggregation, now built into Advanced Container Networking Services and contributed upstream to Hubble for the open-source community, groups similar flows into summarized records every 30 seconds. The result is dramatically reduced data volume while preserving security verdicts, service identity, and error context. What previously required custom post-processing pipelines is now built directly into the platform before storage costs are incurred. Every matched flow log captures: source and destination pods, namespaces, ports, protocols, traffic direction, and policy verdicts. Logs are stored in a Log Analytics workspace (ContainerNetworkLogs table) with a choice of using the Analytics or Basic tier. Built-in Azure portal dashboards are available for both tiers. Logs can also be exported to external log collectors such as Splunk or Datadog. First to Market: Azure and the upstream Hubble Contribution Advanced Container Networking Services built-in filtering and aggregation capabilities were engineered from the ground up to solve real production observability challenges at scale. Rather than keeping this innovation proprietary, Azure contributed the log aggregation and filtering capabilities to the upstream Hubble project, the observability layer of the Cilium ecosystem. This means: AKS customers get a fully managed, Azure-native experience with portal dashboards, Log Analytics integration, and Grafana visualization, out of the box. The broader open-source community gains access to the same filtering and aggregation primitives through upstream Hubble. Azure is the first to ship this capability in a managed Kubernetes service, and the first to give it back to the community. Key Benefits 💰 Lower observability cost. Metrics filtering drops unwanted data on the node before Prometheus ever scrapes it. Flow log aggregation compresses log data by up to 97% in lab testing. Your cost scales with what you choose to monitor, not with cluster size. 📉 Less noise, more signal. Metrics filtering carves out the namespaces and workloads that matter, so dashboards show only relevant signals. Log filters scope collection to specific pods and verdicts. Engineers start every investigation with data that's already relevant. ⚡ Faster root-cause isolation. Every metric carries source and destination pod context. Targeted flow logs add the forensic detail, which policy, destination, or port is involved. Together, they cut mean time to resolution from hours of guesswork to minutes of structured investigation. 🔒 Full signal, zero gaps. Within the scope you define, every flow is captured and every pattern is preserved. Aggregation compresses volume without losing security verdicts or error context. Who Benefits Platform engineers managing multi-tenant clusters can scope data collection per namespace, so each team gets visibility into their own traffic without contributing to a shared cost pool. SREs can isolate packet drops, TCP resets, or DNS failures to a specific workload in minutes, starting with data that's already scoped to what matters. Decision-makers evaluating observability spend get predictable, controllable ingestion costs that scale with intent, not infrastructure size. How to optimize metrics and logs with filtering? Enable Advanced Container Networking Services ( ACNS) on your AKS cluster with the Cilium data plane: az aks create --enable-acns Or on an existing cluster: az aks update --resource-group $RESOURCE_GROUP --name $CLUSTER --enable-acns Apply a ContainerNetworkMetric CRD to filter which metrics are collected on each node. Start by excluding noisy system namespaces, then scope to business-critical workloads. Apply a ContainerNetworkLog CRD to define which flows to capture. Enable Azure Monitor integration with --enable-container-network-logs to send logs to a Log Analytics workspace, or export logs from the node to an external logging system such as Splunk or Datadog. Check your dashboards. Open your cluster in the Azure portal and go to Monitor > Insights > Networking for bytes, drops, DNS errors, and flows. For flow logs, use the built-in Azure portal dashboards available for both Basic and Analytics tiers. Conclusion Kubernetes network observability has long meant choosing between visibility and cost. With container network metrics filtering and log filtering and aggregation now GA in Advanced Container Networking Services (ACNS) and contributed to upstream Hubble for the open-source community, that tradeoff is gone. Azure is first to market with this capability. AKS customers get it fully managed, out of the box, with built-in dashboards with Log Analytics integration. And the broader Cilium ecosystem gets it through upstream Hubble. High-fidelity visibility. Lower cost. No compromise. Learn more: Container network metrics overview: Container network metrics overview - Azure Kubernetes Service | Microsoft Learn Container network logs overview: Container Network Logs Overview - Azure Kubernetes Service | Microsoft Learn Configure container network metrics filtering: Configure Container network metrics filtering for Azure Kubernetes Service (AKS) - Azure Kubernetes Service | Microsoft Learn Set up container network logs: Set up container network logs - Azure Kubernetes Service | Microsoft Learn
Security Review for Microsoft Edge version 148
We have reviewed the new settings in Microsoft Edge version 148 and determined that there are no additional security settings that require enforcement. The Microsoft Edge version 139 security baseline continues to be our recommended configuration which can be downloaded from the Microsoft Security Compliance Toolkit. Microsoft Edge version 148 introduced 16 new Computer and User settings; we have included a spreadsheet listing the new settings to make it easier for you to find. As a friendly reminder, all available settings for Microsoft Edge are documented here, and all available settings for Microsoft Edge Update are documented here. Please continue to give us feedback through the Security Baselines Discussion site or this post.Windows 11, version 25H2 security baseline
Microsoft is pleased to announce the security baseline package for Windows 11, version 25H2! You can download the baseline package from the Microsoft Security Compliance Toolkit, test the recommended configurations in your environment, and customize / implement them as appropriate. Summary of changes This release includes several changes made since the Windows 11, version 24H2 security baseline to further assist in the security of enterprise customers, to include better alignment with the latest capabilities and standards. The changes include what is depicted in the table below. Security Policy Change Summary Printer: Impersonate a client after authentication Add “RESTRICTED SERVICES\PrintSpoolerService” to allow the Print Spooler’s restricted service identity to impersonate clients securely NTLM Auditing Enhancements Enable by default to improve visibility into NTLM usage within your environment MDAV: Attack Surface Reduction (ASR) Add "Block process creations originating from PSExec and WMI commands" (d1e49aac-8f56-4280-b9ba-993a6d77406c) with a recommended value of 2 (Audit) to improve visibility into suspicious activity MDAV: Control whether exclusions are visible to local users Move to Not Configured as it is overridden by the parent setting MDAV: Scan packed executables Remove from the baseline because the setting is no longer functional - Windows always scans packed executables by default Network: Configure NetBIOS settings Disable NetBIOS name resolution on all network adapters to reduce legacy protocol exposure Disable Internet Explorer 11 Launch Via COM Automation Disable to prevent legacy scripts and applications from programmatically launching Internet Explorer 11 using COM automation interfaces Include command line in process creation events Enable to improve visibility into how processes are executed across the system WDigest Authentication Remove from the baseline because the setting is obsolete - WDigest is disabled by default and no longer needed in modern Windows environments Printer Improving Print Security with IPPS and Certificate Validation To enhance the security of network printing, Windows introduces two new policies focused on controlling the use of IPP (Internet Printing Protocol) printers and enforcing encrypted communications. The setting, "Require IPPS for IPP printers", (Administrative Templates\Printers) determines whether printers that do not support TLS are allowed to be installed. When this policy is disabled (default), both IPP and IPPS transport printers can be installed - although IPPS is preferred when both are available. When enabled, only IPPS printers will be installed; attempts to install non-compliant printers will fail and generate an event in the Application log, indicating that installation was blocked by policy. The second policy, "Set TLS/SSL security policy for IPP printers" (same policy path) requires that printers present valid and trusted TLS/SSL certificates before connections can be established. Enabling this policy defends against spoofed or unauthorized printers, reducing the risk of credential theft or redirection of sensitive print jobs. While these policies significantly improve security posture, enabling them may introduce operational challenges in environments where IPP and self-signed or locally issued certificates are still commonly used. For this reason, neither policy is enforced in the security baseline, at this time. We recommend that you assess your printers, and if they meet the requirements, consider enabling those policies with a remediation plan to address any non-compliant printers in a controlled and predictable manner. User Rights Assignment Update: Impersonate a client after authentication We have added RESTRICTED SERVICES\PrintSpoolerService in the “Impersonate a client after authentication” User Rights Assignment policy. The baseline already includes Administrators, SERVICE, LOCAL SERVICE, and NETWORK SERVICE for this user right. Adding the restricted Print Spooler supports Microsoft’s ongoing effort to apply least privilege to system services. It enables Print Spooler to securely impersonate user tokens in modern print scenarios using a scoped, restricted service identity. Although this identity is associated with functionality introduced as part of Windows Protected Print (WPP), it is required to support proper print operations even if WPP is not currently enabled. The system manifests the identity by default, and its presence ensures forward compatibility with WPP-based printing. Note: This account may appear as a raw SID (e.g., S-1-5-99-...) in Group Policy or local policy tools before the service is fully initialized. This is expected and does not indicate a misconfiguration. Warning: Removing this entry will result in print failures in environments where WPP is enabled. We recommend retaining this entry in any custom security configuration that defines this user right. NTLM Auditing Enhancements Windows 11, version 25H2 includes enhanced NTLM auditing capabilities, enabled by default, which significantly improves visibility into NTLM usage within your environment. These enhancements provide detailed audit logs to help security teams monitor and investigate authentication activity, identify insecure practices, and prepare for future NTLM restrictions. Since these auditing improvements are enabled by default, no additional configuration is required, and thus the baseline does not explicitly enforce them. For more details, see Overview of NTLM auditing enhancements in Windows 11 and Windows Server 2025. Microsoft Defender Antivirus Attack Surface Reduction (ASR) In this release, we've updated the Attack Surface Reduction (ASR) rules to add the policy Block process creations originating from PSExec and WMI commands (d1e49aac-8f56-4280-b9ba-993a6d77406c) with a recommended value of 2 (Audit). By auditing this rule, you can gain essential visibility into potential privilege escalation attempts via tools such as PSExec or persistence mechanisms using WMI. This enhancement helps organizations proactively identify suspicious activities without impacting legitimate administrative workflows. Control whether exclusions are visible to local users We have removed the configuration for the policy "Control whether exclusions are visible to local users" (Windows Components\Microsoft Defender Antivirus) from the baseline in this release. This change was made because the parent policy "Control whether or not exclusions are visible to Local Admins" is already set to Enabled, which takes precedence and effectively overrides the behavior of the former setting. As a result, explicitly configuring the child policy is unnecessary. You can continue to manage exclusion visibility through the parent policy, which provides the intended control over whether local administrators can view exclusion lists. Scan packed executables The “Scan packed executables” setting (Windows Components\Microsoft Defender Antivirus\Scan) has been removed from the security baseline because it is no longer functional in modern Windows releases. Microsoft Defender Antivirus always scans packed executables by default, therefore configuring this policy has no effect on the system. Disable NetBIOS Name Resolution on All Networks In this release, we start disabling NetBIOS name resolution on all network adapters in the security baseline, including those connected to private and domain networks. The change is reflected in the policy setting “Configure NetBIOS settings” (Network\DNS Client). We are trying to eliminate the legacy name resolution protocol that is vulnerable to spoofing and credential theft. NetBIOS is no longer needed in modern environments where DNS is fully deployed and supported. To mitigate potential compatibility issues, you should ensure that all internal systems and applications use DNS for name resolution. We recommend the following; test critical workflows in a staging environment prior to deployment, monitor for any resolution failures or fallback behavior, and inform support staff of the change to assist with troubleshooting as needed. This update aligns with our broader efforts to phase out legacy protocols and improve security. Disable Internet Explorer 11 Launch Via COM Automation To enhance the security posture of enterprise environments, we recommend disabling Internet Explorer 11 Launch Via COM Automation (Windows Components\Internet Explorer) to prevent legacy scripts and applications from programmatically launching Internet Explorer 11 using COM automation interfaces such as CreateObject("InternetExplorer.Application"). Allowing such behavior poses a significant risk by exposing systems to the legacy MSHTML and ActiveX components, which are vulnerable to exploitation. Include command line in process creation events We have enabled the setting "Include command line in process creation events" (System\Audit Process Creation) in the baseline to improve visibility into how processes are executed across the system. Capturing command-line arguments allows defenders to detect and investigate malicious activity that may otherwise appear legitimate, such as abuse of scripting engines, credential theft tools, or obfuscated payloads using native binaries. This setting supports modern threat detection techniques with minimal performance overhead and is highly recommended. WDigest Authentication We removed the policy "WDigest Authentication (disabling may require KB2871997)" from the security baseline because it is no longer necessary for Windows. This policy was originally enforced to prevent WDigest from storing user’s plaintext passwords in memory, which posed a serious credential theft risk. However, starting with 24H2 update, the engineering teams deprecated this policy. As a result, there is no longer a need to explicitly enforce this setting, and the policy has been removed from the baseline to reflect the current default behavior. Since the setting does not write to the normal policies location in the registry it will not be cleaned up automatically for any existing deployments. Please let us know your thoughts by commenting on this post or through the Security Baseline Community.Introducing Azure Container Apps Express!
Three years ago, a 15-second cold start was industry-leading. Today, developers and AI agents expect sub-second. The speed bar has moved, and the tooling needs to move with it. After running Azure Container Apps for years, we've learned something important: for most developers, the ACA environment is an unnecessary construct. It adds provisioning time, configuration surface, and cognitive overhead — when all you really want is to run your app with scaling, networking, and operations handled for you. At the same time, a new class of workloads has emerged. Agent-first platforms — systems where AI agents deploy endpoints on demand, spin up tool-use APIs, and tear them down when work is done — demand an even more radical focus on speed and simplicity. Every second of provisioning delay is wasted agent productivity. Today, we're launching Azure Container Apps Express in Public Preview — the fastest, simplest way to go from a container image to an internet-reachable app on Azure, ready for many production-style workloads. What Is ACA Express? ACA Express removes the infrastructure decisions. There's no environment to provision, no networking to configure, no scaling rules to write. You bring a container image, Express handles everything else. Behind the scenes, Express runs your container on pre-provisioned capacity with sensible defaults baked in — so you skip environment setup without giving up ACA's serverless model. There's more coming in this space soon — keep watching. Here's what that means in practice: Instant provisioning — your app is running in seconds, not minutes Sub-second cold starts — fast enough for interactive UIs and on-demand agent endpoints Scale to and from zero — automatic, no configuration required (full scaling controls coming soon) Per-second billing — pay only for what you use Production-ready defaults — ingress, secrets, environment variables, and observability are built in Express is purpose-built for two audiences: developers who want to ship fast (SaaS apps, APIs, web dashboards, prototypes) and agents that deploy on demand (MCP servers, tool-use endpoints, multi-step workflow APIs, human-in-the-loop UIs). If you've ever waited for an ACA environment to provision, only to realize you didn't need half of the configuration options it asked you for — Express is your answer. What You Can Do Today Note: West Central US is currently the only available region. We will expand to new regions through the coming days. Express is in Public Preview starting today. It's a deliberate early ship — there's a meaningful feature gap compared to the existing Azure Container Apps offering, and we're filling it fast. New capabilities are landing on a rapid cadence throughout the preview, and by Microsoft Build in June, Express should be close to feature-complete. For the current list of supported features, known gaps, and what's on the way, see the Express documentation. We'd rather put valuable technology in your hands early and iterate with you than wait behind closed doors for perfection. Who Is Express For? Scenario Why Express SaaS apps and APIs Deploy and scale without infrastructure planning AI app frontends Chat UIs and copilot frontends that scale with usage spikes MCP servers Expose API endpoints for AI agents in seconds Agent workflows Spin up endpoints on demand, tear down when done Prototypes and startups Go from idea to production in minutes Web dashboards Internal tools with instant availability Get Started Express is available now in Public Preview. Try it: Azure Container Apps Express overview — concepts, capabilities, and the current feature support matrix Deploy your first app with the Azure CLI — step-by-step quickstart New Azure Container Apps Portal — create and manage Express apps alongside your existing Container Apps resources Have questions? Check the Azure Container Apps Express FAQ for answers to common questions about pricing, limits, regions, and the road to GA. We're building Express in the open and we want to hear from you. Tell us what features matter most, what works, and what doesn't — reach out on the Azure Container Apps GitHub or in the comments below.
Azure virtual network terminal access point (TAP) public preview announcement
What is virtual network TAP? Virtual network TAP allows customers continuously stream virtual machine network traffic to a network packet collector or analytics tool. Many security and performance monitoring tools rely on packet-level insights that are difficult to access in cloud environments. Virtual network TAP bridges this gap by integrating with our industry partners to offer: Enhanced security and threat detection: Security teams can inspect full packet data in real-time to detect and respond to potential threats. Performance monitoring and troubleshooting: Operations teams can analyze live traffic patterns to identify bottlenecks, troubleshoot latency issues, and optimize application performance. Regulatory compliance: Organizations subject to compliance frameworks such as Health Insurance Portability and Accountability Act (HIPAA), and General Data Protection Regulation (GDPR) can use virtual network TAP to capture network activity for auditing and forensic investigations. Why use virtual network TAP? Unlike traditional packet capture solutions that require deploying additional agents or network appliances, virtual network TAP leverages Azure's native infrastructure to enable seamless traffic mirroring without complex configurations and without impacting the performance of the virtual machine. A key advantage is that mirrored traffic does not count towards virtual machine’s network limits, ensuring complete visibility without compromising application performance. Additionally, virtual network TAP supports all Azure virtual machine SKU. Deploying virtual network TAP The portal is a convenient way to get started with Azure virtual network TAP. However, if you have a lot of Azure resources and want to automate the setup you may want to use a PowerShell, CLI, or REST API. Add a TAP configuration on a network interface that is attached to a virtual machine deployed in your virtual network. The destination is a virtual network IP address in the same virtual network as the monitored network interface or a peered virtual network. The collector solution for virtual network TAP can be deployed behind an Azure Internal Load balancer for high availability. You can use the same virtual network TAP resource to aggregate traffic from multiple network interfaces in the same or different subscriptions. If the monitored network interfaces are in different subscriptions, the subscriptions must be associated to the same Microsoft Entra tenant. Additionally, the monitored network interfaces and the destination endpoint for aggregating the TAP traffic can be in peered virtual networks in the same region. Partnering with industry leaders to enhance network monitoring in Azure To maximize the value of virtual network TAP, we are proud to collaborate with industry-leading security and network visibility partners. Our partners provide deep packet inspection, analytics, threat detection, and monitoring solutions that seamlessly integrate with virtual network TAP: Network packet brokers Partner Product Gigamon GigaVUE Cloud Suite for Azure Keysight CloudLens Security analytics, network/application performance management Partner Product Darktrace Darktrace /NETWORK Netscout Omnis Cyber Intelligence NDR Corelight Corelight Open NDR Platform LinkShadow LinkShadow NDR Fortinet FortiNDR Cloud FortiGate VM cPacket cPacket Cloud Suite TrendMicro Trend Vision One™ Network Security Extrahop RevealX Bitdefender GravityZone Extended Detection and Response for Network eSentire eSentire MDR Vectra Vectra NDR AttackFence AttackFence NDR Arista Networks Arista NDR See our partner blogs: Bitdefender + Microsoft Virtual Network TAP: Deepening Visibility, Strengthening Security Streamline Traffic Mirroring in the Cloud with Azure Virtual Network Terminal Access Point (TAP) and Keysight Visibility | Keysight Blogs eSentire | Unlocking New Possibilities for Network Monitoring and… LinkShadow Unified Identity, Data, and Network Platform Integrated with Microsoft Virtual Network TAP Extrahop and Microsoft Extend Coverage for Azure Workloads Resources | Announcing cPacket Partnership with Azure virtual network terminal access point (TAP) Gain Network Traffic Visibility with FortiGate and Azure virtual network TAP Get started with virtual network TAP To learn more and get started, visit our website. We look forward to seeing how you leverage virtual network TAP to enhance security, performance, and compliance in your cloud environment. Stay tuned for more updates as we continue to refine and expand on our feature set! If you have any questions please reach out to us at azurevnettap@microsoft.com.
Public Preview Update: Azure Copilot Observability Agent
Modern cloud applications generate massive amounts of telemetry - metrics, logs, traces, alerts, and platform signals. Yet whether you're asking questions about your observability data or responding when things go wrong, discovering insights and root causes requires a deep understanding of the application, the observability signals it emits, and the tools, while your business and customers are impacted. The Observability agent is designed to be your monitoring companion across the full observability lifecycle, enabling you to interact via chat to better understand your observability data. Our aspiration is to support the full range of activities - from onboarding and detection through triage and root cause analysis - to significantly reduce human toil and customer downtime. Today, the agent already covers key investigation and exploration scenarios, and we’re rapidly expanding its capabilities across more workflows and entry points. Deep, agentic investigations Deep investigations are designed for situations where something is already wrong and the goal is to understand what happened and what to do next The Observability agent is optimized for real‑world, full‑stack investigations in distributed systems - including environments built on Azure Kubernetes Service (AKS) and Virtual Machines (VMs). To discover the root cause, the agent applies deep reasoning, using an innovative array of Machine Learning (ML) and Large Language Models (LLM) to discover and correlate anomalies across huge volume of signals across application, infrastructure, and Azure platform layers to converge on likely root‑cause candidates across scenarios such as: Application issues, including deployment and performance regressions, request or dependency failures, resource exhaustion, and identity or configuration errors Infrastructure issues, such as compute saturation, disk I/O throttling, misconfigured dependencies, or network connectivity failures in AKS clusters and VMs Platform incidents, including Azure maintenance or outages and managed infrastructure issues like SNAT port exhaustion or upgrade blockers The easiest way to start a deep investigation is directly from an Azure Monitor alert, whether in the Azure portal or from an alert notification. Investigations can also be initiated from other entry points – e.g. the agent chat, Logs, Activity logs with additional entry points being added over time When a deep investigation runs, the agent produces an investigation report that captures the analysis, root cause, suggested next steps along with the key signals, and supporting data. The agent also surfaces a granular insight into its reasoning / chain-of-thought, including data accessed, queries run and more. User does not need to stop there – they can continue interacting with the agent, in the context of investigation to explore deeper or guide agent into additional hypothesis: What changed shortly before the incident started? Are there any issues in VM <vm_id> and are they related? If yes, run a deep investigation including this VM Which dependencies are most correlated with this failure spike? Are there related alerts or configuration changes that explain this behavior? Investigation results can be saved as an Azure Monitor Issue, preserving the full investigation context for collaboration and continuity. Data exploration and analytics The Observability agent supports data exploration and analytics for ad‑hoc understanding and hypothesis building, without starting from an alert or running a full investigation. To get started, simply click on the “Observability Agent” button from the Logs blade (or other supported entry points). From there, you can explore observability data such as logs and metrics using natural language prompts like: Show the top errors over the last hour Is there a correlation between application errors and dependency errors? Chart the trend of application errors and storage related errors What operations in my app are impacted by the ongoing authentication issue? Find latency spikes in my app over the last 3 days and where they are coming from (specific users or regions) If you already had a query / query results in Logs blade – the agent will pick it up automatically, and you can ask it to explain the results, help you evolve the query or even optimize it. Moreover, when exploration surfaces a broader or more complex problem, operators can choose to run a deep investigation directly from the exploration context and persist the results as an Issue. Looking ahead We’re continuing to expand the Observability agent to cover more of the observability lifecycle, moving from reactive investigation toward more proactive and continuous system understanding: Deeper integration across Azure Monitor experiences Expanding beyond alerts into additional entry points and workflows across the platform Autonomous observability When signals indicate emerging or ongoing incidents, the agent can proactively correlate alerts, run investigations, and create Azure Monitor Issues automatically - reducing the need for manual triage Integration with external systems Extending investigation context beyond Azure Monitor, so insights and conclusions can flow into existing engineering workflows Stay connected Follow this blog for ongoing deep dives, updates on current capabilities, and a preview of what’s coming next. Live webinar A walkthrough of real Observability agent scenarios, best practices, and what’s available today - along with a look at what’s coming next, and live Q&A with the product team. 👉 Register here We’d love your feedback The Observability agent continues to evolve based on real‑world usage and operator feedback. Share your thoughts directly through the Give Feedback option in the experience, or reach us at: azureobsagent@microsoft.comBuild Smarter, Simpler IoT Messaging with Azure Event Grid MQTT Broker
Why this matters for modern IoT solutions As IoT solutions grow, teams need messaging that is reliable, scalable, and simple enough to operate across devices, apps, and cloud services. Azure Event Grid MQTT broker helps organizations connect devices and applications using standard MQTT patterns while also integrating with Azure services for downstream processing and automation. The result is a managed, cloud-native approach to messaging that supports both technical flexibility and business agility. With support for MQTT v3.1.1 and MQTT v5, Azure Event Grid MQTT broker enables device-to-device, device-to-cloud, and server-to-device communication patterns. It is especially useful in scenarios where customers want to ingest telemetry, send commands, broadcast alerts, and route data into analytics or workflow systems without building and maintaining broker infrastructure themselves. In this post, we focus on four capabilities that make the experience even more powerful and easier to adopt: MQTT Retain support, Shared Subscriptions, HTTP Publish of MQTT messages, and Subscription Identifiers. These features help new subscribers get context immediately, allow multiple consumers to scale out work, let HTTP-native back-end services participate in MQTT workflows, and make message handling more efficient for clients. Four features that make MQTT messaging easier to use These capabilities are designed to solve everyday problems that customers face when building real-world IoT systems. MQTT Retain support helps newly connected clients get the latest known value right away. Shared Subscriptions help distribute message processing across multiple consumers for better scale and resilience. HTTP Publish of MQTT messages enables back-end services to send MQTT messages without keeping long-lived MQTT sessions open. Subscription Identifiers help clients understand which subscription matched a received message, making routing and processing simpler. Together, these features reduce application complexity, improve responsiveness, and make it easier for teams to build user-friendly, production-ready IoT experiences. MQTT Retain support: Give new subscribers the latest known value instantly One of the most helpful MQTT patterns is the ability to retain the latest message on a topic. With MQTT Retain support in Azure Event Grid, the broker stores the last known good value for a topic and delivers it immediately to a new subscriber. That means a client does not have to wait for the next live publish to understand the current state. This is especially valuable for scenarios such as device state, configuration settings, last reported sensor readings, and control values. When a new application, dashboard, or device comes online, it can immediately understand the current state of the system and take action faster. Example Imagine a smart factory dashboard subscribing to the topic factory/line1/status. If the latest retained message says Running, a newly opened dashboard can display that status immediately instead of waiting for the next update. Retained messages ensure new subscribers instantly receive the latest device state without waiting for the next publish Why customers like it Faster onboarding for newly connected devices and apps Better user experience in dashboards and operator tools Less waiting for current state information Simpler application logic for recovering context Common use cases Device online or offline state Latest environmental reading such as temperature or humidity Machine mode, recipe, or configuration profile Current command state for field equipment Shared Subscriptions: Scale message processing without extra complexity As message volume grows, a single subscriber may not be enough to process all incoming data efficiently. Shared Subscriptions solve this by allowing multiple consumers to share the work for a subscription. Instead of every consumer receiving every message, the broker distributes messages across members of the shared group. This is a powerful pattern for scaling out telemetry processing, command handling, or event enrichment pipelines. It also helps improve resilience because work can continue even if one consumer instance goes offline. Example Suppose you have a fleet of connected vehicles publishing telemetry to vehicles/+/telemetry. A back-end processing service might run three worker instances subscribed through a shared subscription. Rather than each worker processing all messages, the workload is divided across the three instances, which improves throughput and reduces duplicate effort. Shared subscriptions distribute telemetry messages across multiple worker nodes for scalable, load-balanced, and resilient stream processing. Why customers like it Easier horizontal scaling for high-volume topics Improved throughput for back-end processing Better fault tolerance for worker-based applications Cleaner architecture for stream processing pipelines Common use cases Telemetry ingestion at scale Alarm processing pipelines Order or command handling across multiple workers Message transformation before routing to analytics platforms Shared Subscriptions help teams grow from pilot projects to production-scale deployments without redesigning their application model. They make it easier to add processing capacity as business needs expand. HTTP Publish of MQTT messages: Bring HTTP-native back-end systems into MQTT workflows Not every application wants to maintain a persistent MQTT connection. Many back-end systems are built around stateless HTTP APIs and prefer simple request-based interactions. Azure Event Grid supports publishing MQTT messages over HTTP, which makes it easier for server-side applications to send messages into MQTT-based solutions. This capability is a strong fit for server-to-device command and control, updates from enterprise systems, and retained message management. It also helps protect broker stability by reducing the need for a large number of long-lived sessions from services that do not truly need them. Example Imagine a support application that needs to send a message to a field device asking it to refresh its configuration. Instead of opening an MQTT session, the application can make an HTTP POST request that maps to an MQTT publish operation and sends the command to the desired topic. Why customers like it Simple integration for HTTP-native applications No need for persistent broker sessions in back-end services Consistent messaging flow across HTTP and MQTT publishers Easier integration with business systems and automation workflows Common use cases Server-to-device commands Application-driven updates and prompts Retained message management Integration with business processes, portals, and line-of-business apps Subscription Identifiers: Make client-side message handling smarter As applications grow, a single client may subscribe to many topic filters at the same time. Subscription Identifiers help the client understand which subscription matched a delivered message. This makes application logic cleaner because the client does not have to guess why a message arrived or manually compare it against every subscribed filter. In practical terms, this is useful when one client is listening for different kinds of data such as telemetry, alerts, and control acknowledgments. Instead of writing extra parsing logic, the client can use the identifier to route the message to the right processing path immediately. Example A monitoring application subscribes to one filter for devices/+/telemetry and another for devices/+/alerts. When a message arrives, the subscription identifier helps the application know whether the message should be shown on a live dashboard, routed to alert handling, or stored for analysis. Why customers like it Simpler client code Cleaner separation of processing paths Easier troubleshooting and observability Better support for sophisticated MQTT v5 client applications Common use cases Applications subscribing to multiple topic categories Edge gateways handling mixed streams Dashboards that separate operational data from alerts Services that apply different business logic based on subscription intent Putting it all together: A simple customer scenario Consider a smart manufacturing plant. Machines, PLCs, and industrial sensors continuously publish telemetry such as production counts, machine health, vibration, and temperature. Operations dashboards subscribe to real-time machine status and line performance. Maintenance systems send commands to equipment when anomalies or thresholds are detected. Meanwhile, analytics workers process high-volume telemetry streams in parallel for quality monitoring, predictive maintenance, and throughput optimization. In this scenario, MQTT Retain support ensures that a newly opened operations dashboard immediately sees the latest machine state without waiting for the next update. Shared Subscriptions enable multiple analytics workers to process telemetry streams in parallel, improving scalability and avoiding duplicate processing. HTTP Publish of MQTT messages allows MES or maintenance applications to send commands to machines through simple HTTP requests, without needing a persistent MQTT connection. Subscription Identifiers help downstream systems distinguish between telemetry, alerts, and control signals, enabling clean routing to the right processing pipelines. The result is a unified, event-driven architecture that is scalable, efficient, and easier to operate—supporting real-time visibility, faster decision-making, and continuous optimization across the manufacturing floor. Azure Event Grid MQTT broker continues to make cloud-scale MQTT messaging more approachable for customers building modern IoT and event-driven solutions. Features such as MQTT Retain support, Shared Subscriptions, HTTP Publish of MQTT messages, and Subscription Identifiers help simplify application design while improving responsiveness, scale, and operational efficiency. For teams looking to build customer-ready solutions faster, these capabilities can reduce custom code, accelerate onboarding, and create a smoother path from proof of concept to production. Whether you are building connected products, industrial monitoring systems, smart spaces, or data-driven operations, Azure Event Grid MQTT broker provides a flexible foundation for reliable communication across devices, services, and applications. Now is a great time to explore how these features can help simplify your architecture and unlock new patterns for device connectivity and cloud integration.Announcing Microsoft Azure Network Adapter (MANA) support for Existing VM SKUs
As a leader in cloud infrastructure, Microsoft ensures that Azure’s IaaS customers always have access to the latest hardware. Our goal is to consistently deliver technology to support business critical workloads with world class efficiency, reliability, and security. Customers benefit from cutting-edge performance enhancements and features, helping them to future proof their workloads while maintaining business continuity. Starting on August 1st, 2026, Azure will start deploying new hardware with Microsoft Azure Network Adapter (MANA), for existing VM Size Families. The intent is to provide the benefits of new server hardware to customers of existing VM SKUs as they work towards migrating to newer SKUs. The deployments will be based on capacity needs and won’t be restricted by region. Once the hardware is available in a region, VMs can be deployed to it as needed. Workloads on operating systems which fully support MANA will benefit from sub-second Network Interface Card (NIC) firmware upgrades, higher throughput, lower latency, increased Security and Azure Boost-enabled data path accelerations. If your workload doesn't support MANA today, you'll still be able to access Azure’s network on MANA enabled SKUs, but performance will be comparable to previous generation (non-MANA) hardware. Check out the Azure Boost Overview and the Microsoft Azure Network Adapter (MANA) overview for more detailed information and OS compatibility. To determine whether your VMs are impacted and what actions (if any) you should take, start with MANA support for existing VM SKUs. This article provides additional information about which VM Sizes are eligible to be deployed on the new MANA-enabled hardware, what actions (if any) you should take, and how to determine if the workload has been deployed on MANA-enabled hardware.
