Azure Local Node - Install Extension Failed

Question

Hi Expert,

I am trying to create an Azure Local cluster with Azure Arc Gateway, but the extension installation is failing.

I have already verified connectivity using azcmagent check, and all required endpoints appear to be reachable.

However, I noticed something unusual in the arcproxy.log. The node is attempting to connect to guestnotificationservice.azure.com and southeastasia-gas.guestconfiguration.azure.com, as shown below:

time=2026-08-06T04:15:13.334Z level=INFO msg="P:1:C:24 127.0.0.1:49907 --> guestnotificationservice.azure.com:443 on HTTP-1.1, User-Agent: Go-http-client/1.1, Via: direct(ts:true)"

time=2026-08-06T04:15:13.662Z level=INFO msg="P:1:C:24 done via direct(ts:true) bytes ->:1522, <-:0"

time=2026-08-06T04:15:14.048Z level=INFO msg="P:1:C:25 127.0.0.1:49910 --> southeastasia-gas.guestconfiguration.azure.com:443 on HTTP-1.1, User-Agent: Go-http-client/1.1, Via: direct(ts:true)"

time=2026-08-06T04:15:14.050Z level=ERROR msg="P:1:C:25 done via direct w/ error - error dialing southeastasia-gas.guestconfiguration.azure.com:443: dial tcp: lookup southeastasia-gas.guestconfiguration.azure.com: no such host"

time=2026-08-06T04:15:14.094Z level=INFO msg="P:1:C:26 127.0.0.1:49912 --> agentserviceapi.guestconfiguration.azure.com:443 on HTTP-1.1, User-Agent: Go-http-client/1.1, Via: direct(ts:true)"

time=2026-08-06T04:15:14.141Z level=INFO msg="P:1:C:26 done via direct(ts:true) bytes ->:1532, <-:0"

The extension installation fails as a result of this issue. as far as i know, this url southeastasia-gas.guestconfiguration.azure.com is not needed to be whitelisted if we are using arc gateway.

Any guidance or recommendations would be appreciated.

Thanks

Answer 1

For Azure Local with Arc gateway, azcmagent check is the correct first validation. The expected successful state is:

1. azcmagent show
   • Agent version: 1.45 or later
   • Agent Status: Connected
   • Using HTTPS Proxy: http://localhost:40343
   • Azure Arc Proxy: running
2. azcmagent check
   • connection.type should be gateway
   • Reachable should be true for all URLs reported by the check

For endpoint allowlisting during Azure Local deployment with Arc gateway, the documented required endpoints are the Azure Arc registration, Arc gateway, Key Vault, storage, and certificate revocation endpoints listed for Azure Local deployment. The provided allowlist does not include southeastasia-gas.guestconfiguration.azure.com.

Since the failure is happening during extension installation, use the VM extension troubleshooting path next:

1. In Azure portal, open the affected Arc-enabled machine and go to Settings > Extensions to inspect the extension state.
2. On the node, run azcmagent show and confirm dependent services are running. If any services other than Azure Arc Proxy are stopped, restart them.
3. Check Guest agent logs from the time of the failed install:
   • Windows: %SystemDrive%\ProgramData\GuestConfig\ext_mgr_logs
   • Extension logs: C:\ProgramData\GuestConfig
   • Extension settings/status: C:\Packages\Plugins
4. Review ...GuestConfig\ext_mgr_logs\gc_ext.log for package download or verification errors.
5. If the extension state is not Succeeded, remove the failed extension and install it again:

Remove-AzConnectedMachineExtension -Name <Extension Name> -ResourceGroupName <RG Name> -MachineName <Machine Name>

6. Also review c:\programdata\AzureConnectedMAchineAgent\Log\arcproxy.log to confirm which endpoints are redirected through the Arc gateway versus sent direct.

Based on the documented Azure Local Arc gateway verification and endpoint list, the supported conclusion is:

• Arc gateway validation is based on azcmagent show, azcmagent check, and arcproxy.log.
• The documented Azure Local required endpoint list does not show southeastasia-gas.guestconfiguration.azure.com.
• The next supported action is extension-level troubleshooting through GuestConfig and extension logs, then retrying the extension installation.

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• About Azure Arc gateway for Azure Local
• Troubleshoot Azure Arc-enabled servers VM extension issues
• Register Azure Local with Azure Arc using Arc gateway (register-proxy)