Azure Local cluster 2025.10 Feature Update failing during post-update validation 'ValidateAndTuneNetworkATCAndClusterConfigurationPostUpdate'

[torgeir345]

The 2510 update ran, and OS seems to be updated on all nodes, but failed during the post-update validation step:

Check Network ATC and Cluster readiness after server OS upgraded

Error shown:
Type 'ValidateAndTuneNetworkATCAndClusterConfigurationPostUpdate' of Role 'HostNetwork' raised an exception.

Main failure:
Invoke-Command -ComputerName azcluster -Credential ...
returned:
The request is not supported
PSRemotingTransportException
FullyQualifiedErrorId : 50,PSSessionStateBroken

Troubleshooting already completed:

DNS resolution for cluster name works
Ping to cluster name works
Test-WSMan azcluster works
Invoke-Command -ComputerName azcluster { hostname } works
All cluster nodes are Up
No active Storage Jobs
Get-NetIntentStatus shows all intents healthy:

ConfigurationStatus = Success
ProvisioningStatus = Completed

Retry of the update fails, and cannot procedd with further updates.

MS-support request 2604280050001156 have been sitting for three weeks with no progress.

Production environment:

3-node Azure Local cluster
Current version before update: 2509
Target update: 2510 Feature Update