Azure Local Duplicate Hostname

Handian Sudianto 7,461 Reputation points
2026-09-13T01:08:13.23+00:00

I have 2 Azure Local Nodes, let say :

  • Node02 with IP 10.10.10.2 and hostname azlocal02
  • Node03 with IP 10.10.10.3 and hostname azlocal03

Then i reboot node03 and after rebooted i try access using KVM or by RDP and i realized Node02 is showing. My assumption is Node2 is take over of ip 10.10.10.3 and i feel strange, so access to 10.10.10.2 and 10.10.10.3 the node2 is showing.

I try do deep checking and i execute ipconfig /all and found the mac address is different even on one console i access node02 and the other access node03.

With this situation even i access to 10.10.0.3 and node02 is showing then i believe this is not real node02 due the mac address is different. Then i try to see the log and found node03 is renamed to node02 in time when i reboot the node03.

When i have 2 same hostname in azure local then the cluster for node03 is down because the cluster maybe try connect to 10.10.10.3 but the hostname is not node03

User's image

User's image

I Access from azure portal then i go to Azure Arc, click the azlocal03 then in the detail node02 is showing. Then i try to rename manual node02 on host 10.10.10.3 to azlocal03, reboot the node and the cluster is running well for both nodes.

But the status on the azure arc is node03 not installed and node02 is disconnectedUser's image

Click on node02 then node03 is showing with warning 'This machine appears to be a clone of another Arc-enabled machine and shares the same Azure Resource ID, which isn't supported. Reconnect it as a new resource to resolve.'

User's image

My question is (hope someone expert here can help me) :

  1. Why node03 is renamed to 02 itself?
  2. To fix the issue of not connected azure arc, then it's safe to disconnected and re-register both of the nodes?
Azure Local
0 comments

1 answer

Sort by: Oldest
Most helpful Newest Oldest
  1. David Aniebo 0 Reputation points
    2026-09-13T01:50:11.7733333+00:00

    Node03's disk was likely cloned from Node02's image (or a shared golden image) without running sysprep /generalize first. The rename to "azlocal03" was applied to the running OS but never written into the recovery/unattend partition. A reboot triggered a recovery-style boot pass that reapplied the original baked-in name ("azlocal02"), causing the hostname collision and cluster failure. Arc's clone-detection then flagged it since both machines shared one onboarding identity, that warning isn't a bug, it's working as intended.

    Here are possible fixes to try;

    1. Reboot Node03 a couple more times to confirm the name sticks. If it reverts again, the disk needs proper re-imaging (generalized), don't touch Arc yet
    2. On each node: azcmagent disconnect (use --force-local-only if the Azure resource is already orphaned).
    3. In the portal, delete both broken Machine
    4. Re-register through the Azure Local cluster registration flow (Register-AzStackHCI), not bare azcmagent connect.
    5. Verify Name/Status/Manufacturer match the correct physical hosts.

    Also check for a duplicate machine SID between the two nodes, since it's a common side effect of the same cloning issue.

    Was this answer helpful?

Your answer

Answers can be marked as 'Accepted' by the question author and 'Recommended' by moderators, which helps users know the answer solved the author's problem.