Azure Local Warning: Arc Resource Bridge is offline

Question

Azure Local Warning: Arc Resource Bridge is offline

Richard Beyer 136

I have a 2 node Dell AX-760 Azure Local cluster running Solution12.2607.1003.69.

Checking the Update Readiness for Hotfix Version 12.2607.1003.71 this morning I discovered this warning:

Title

ARCVMStack.ARBStatusUnhealthy

Description

Arc Resource Bridge is offline. Auto-remediation will be attempted. If the issue persists, contact Microsoft Support. NULL

Resource type

Cluster

Individual system results

Cluster/ali-azcluster



Warning

8/4/2026, 12:37 PM

Contact Microsoft Support.

Suggestions?

Thank you,

Richard Beyer

Sujitha Lakkireddy 85 Reputation points Microsoft External Staff Moderator

2026-08-05T15:48:59.82+00:00

Hi Richard,

Thank you for choosing Microsoft Q&A forum.

The warning means the Arc Resource Bridge appliance VM for the Azure Local cluster is currently offline or unhealthy. Since this appears during update readiness, I would not ignore it before proceeding with the hotfix.

A few things to check:

1. Verify that the Arc Resource Bridge appliance VM is running and reachable. If it is offline, restart the appliance VM and then rerun the update readiness check.

2. Check for recent network, firewall, proxy, routing, or DNS changes. An offline Arc Resource Bridge often points to the appliance VM not being able to communicate properly with Azure or required management endpoints.

3. Confirm connectivity from the management machine to the appliance VM. Microsoft’s troubleshooting guidance notes that log collection can fail if the management machine cannot reach the appliance VM over SSH on TCP port 22.

4. Do not delete or recreate the Arc Resource Bridge VM unless Microsoft Support advises it. Microsoft calls Arc Resource Bridge a critical Azure Local component and says it should not be deleted without Microsoft Support guidance.

**References:
** Troubleshoot Azure Arc resource bridge issues - Azure Arc | Microsoft Learn
Richard Beyer 136 Reputation points

2026-08-05T16:58:15.6333333+00:00

Hi Sujitha,

Is this VM the ARC Resource Bridge?

If so, it is "running" but I have included a screenshot of the console that is showing it in an emergency mode.

Should I restart this from the Windows Admin Center or in some other fashion?
Richard Beyer 136 Reputation points

2026-08-06T22:34:27.8866667+00:00

Thank you Sujitha. I have done a shutdown and power-on for the VM since there was no clean restart option, only reset. The VM did appear to restart cleanly and the Get-ClusterGroup returns "online":

[ali-aznode01]: PS C:\Users\rbeyer-e\Documents> Get-ClusterGroup -Name "b67d7e3c201037ef0b2112df0457905679bd893c97e6e-control-plancmxhm-66d496b5"

Name OwnerNode State

b67d7e3c201037ef0b2112df0457905679bd893c97e6e-control-plancmxhm-66d496b5 ALI-AZNode01 Online

I ran another update readiness check and that is still showing the same warning.

Answer accepted by question author

0 additional answers

Your answer

Sujitha Lakkireddy 85 Reputation points Microsoft External Staff Moderator

2026-08-05T15:48:59.82+00:00

Hi Richard,

Thank you for choosing Microsoft Q&A forum.

The warning means the Arc Resource Bridge appliance VM for the Azure Local cluster is currently offline or unhealthy. Since this appears during update readiness, I would not ignore it before proceeding with the hotfix.

A few things to check:

1. Verify that the Arc Resource Bridge appliance VM is running and reachable. If it is offline, restart the appliance VM and then rerun the update readiness check.

2. Check for recent network, firewall, proxy, routing, or DNS changes. An offline Arc Resource Bridge often points to the appliance VM not being able to communicate properly with Azure or required management endpoints.

3. Confirm connectivity from the management machine to the appliance VM. Microsoft’s troubleshooting guidance notes that log collection can fail if the management machine cannot reach the appliance VM over SSH on TCP port 22.

4. Do not delete or recreate the Arc Resource Bridge VM unless Microsoft Support advises it. Microsoft calls Arc Resource Bridge a critical Azure Local component and says it should not be deleted without Microsoft Support guidance.

**References:
** Troubleshoot Azure Arc resource bridge issues - Azure Arc | Microsoft Learn
Richard Beyer 136 Reputation points

2026-08-05T16:58:15.6333333+00:00

Hi Sujitha,

Is this VM the ARC Resource Bridge?

If so, it is "running" but I have included a screenshot of the console that is showing it in an emergency mode.

Should I restart this from the Windows Admin Center or in some other fashion?
Richard Beyer 136 Reputation points

2026-08-06T22:34:27.8866667+00:00

Thank you Sujitha. I have done a shutdown and power-on for the VM since there was no clean restart option, only reset. The VM did appear to restart cleanly and the Get-ClusterGroup returns "online":

[ali-aznode01]: PS C:\Users\rbeyer-e\Documents> Get-ClusterGroup -Name "b67d7e3c201037ef0b2112df0457905679bd893c97e6e-control-plancmxhm-66d496b5"

Name OwnerNode State

b67d7e3c201037ef0b2112df0457905679bd893c97e6e-control-plancmxhm-66d496b5 ALI-AZNode01 Online

I ran another update readiness check and that is still showing the same warning.

Answer 1

Hi Richard Beyer,

Yes, that looks like the Arc Resource Bridge control-plane/appliance VM based on the control-plan name.

Even though the VM shows as “running,” the console screenshot shows the appliance OS is in emergency mode and failing to mount /sysroot, so the Arc Resource Bridge is not actually healthy.

Please do not manually repair the Linux appliance, run filesystem repair commands, delete/recreate the VM, or restore it from snapshot/backup. Microsoft documentation states that Arc Resource Bridge is a critical Azure Local component and changes/recovery should be done only with Microsoft Support guidance.

You can try one graceful restart of this VM from Windows Admin Center or Failover Cluster Manager, then rerun the update readiness check.

Also check the cluster group status from one of the Azure Local nodes:

Get-ClusterGroup -Name "control-plan"

If the VM returns to emergency mode or the readiness warning remains, please collect logs and share it in private message

References:

https://learn.microsoft.com/en-us/azure/azure-arc/resource-bridge/troubleshoot-resource-bridge

https://learn.microsoft.com/en-us/azure/azure-arc/resource-bridge/maintenance

https://github.com/Azure/AzureLocal-Supportability/blob/main/TSG/Update/Update-fails-with-ARB-offline.md

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