Blog Post

Azure Arc Blog
3 MIN READ

Announcing the preview of Software Defined Networking (SDN) on Azure Local

varunlakshmanan's avatar
Jul 17, 2025

Big news for Azure Local customers!

Starting in Azure Local version 2506, we’re excited to announce the Public Preview of Software Defined Networking (SDN) on Azure Local using the Azure Arc resource bridge. This release introduces cloud-native networking capabilities for access control at the network layer, utilizing Network Security Groups (NSGs) on Azure Local.

Key highlights in this release are:

1- Centralized network management: Manage Logical networks, network interfaces, and NSGs through the Azure control plane – whether your preference is the Azure Portal, Azure Command-Line Interface (CLI), or Azure Resource Manager templates.

2- Fine-grained traffic control: Safeguard your edge workloads with policy-driven access controls by applying inbound and outbound allow/deny rules on NSGs, just as you would in Azure.

3- Seamless hybrid consistency: Reduce operational friction and accelerate your IT staff’s ramp-up on advanced networking skills by using the same familiar tools and constructs across both Azure public cloud and Azure Local.

Software Defined Networking (SDN) forms the backbone of delivering Azure-style networking on-premises. Whether you’re securing enterprise applications or extending cloud-scale agility to your on-premises infrastructure, Azure Local, combined with SDN enabled by Azure Arc, offers a unified and scalable solution. Try this feature today and let us know how it transforms your networking operations!

What’s New in this Preview?

Here’s what you can do today with SDN enabled by Azure Arc:

✅ Run SDN Network Controller as a Failover Cluster service — no VMs required!

✅ Deploy logical networks — use VLAN-backed networks in your datacenter that integrate with SDN enabled by Azure Arc.

✅ Attach VM Network Interfaces — assign static or DHCP IPs to VMs from logical networks.

✅ Apply NSGs - create, attach, and manage NSGs directly from Azure on your logical networks (VLANs in your datacenter) and/or on the VM network interface.  This enables a generic rule set for VLANs, with a crisper rule set for individual Azure Local VM network interface using a complete 5-tuple control: source and destination IP, port, and protocol.

An example of a network security group with inbound and outbound security rules configured

✅ Use Default Network Policies — apply baseline security policies during VM creation for your primary NIC. Select well-known inbound ports such as HTTP (while we block everything else for you), while still allowing outbound traffic.  Or select an existing NSG you already have!

An example of setting a default network policy on the network interface to allow HTTP traffic on port 80 of a virtual machine

SDN enabled by Azure Arc (Preview) vs. SDN managed by on-premises tools

Choosing Your Path: Some SDN features like virtual networks (vNETs), Load Balancers (SLBs), and Gateways are not yet supported in the SDN enabled by Azure Arc (Preview). But good news: you’ve still got options.

If your workloads need those features today, you can leverage SDN managed by on-premises tools:

- SDN Express (PowerShell)

- Windows Admin Center (WAC)

The SDN managed by on-premises tools continues to provide full-stack SDN capabilities, including SLBs, Gateways, and VNET peering, while we actively work on bringing this additional value to complete SDN enabled by Azure Arc feature set.

You must choose one of the modes of SDN management and cannot run in a hybrid management mode, mixing the two. Please read this important consideration section before getting started!

Thank You to Our Community

This milestone was only possible because of your input, your use cases, and your edge innovation. We're beyond excited to see what you build next with SDN enabled by Azure Arc.

To try it out, head to the Azure Local documentation

Let’s keep pushing the edge forward. Together!

Updated Jul 12, 2025
Version 1.0

5 Comments

  • I've a question about the Overview page on the "Associated with" information displayed. 
    My MgmtNSG have associated to one of the Logical Nic, however, the information doesn't shown in this section. 

     

    • varunlakshmanan's avatar
      varunlakshmanan
      Icon for Microsoft rankMicrosoft

      LCKho3693​ Thanks for trying out the feature and posting your question! In the screenshot you shared, you are looking at a logical network object on Azure Local and seeing what NSG is associated to it (in this case it is MgmtNSG)

      On the portal if you navigate to your NIC object (to which you associated this same NSG) and look under "Settings" > "Network Security Groups (preview)", you should see the association you are looking for.

      • LCKho3693's avatar
        LCKho3693
        MVP

        varunlakshmanan​ yes, it does. But when we navigate to Overview page of MgmtNSG the association shows "0" on the Associated with section.

         

  • Thanks for sharing and for showcasing the other options too :-)

    Happy Azure Localling!