vSAN cluster UUID mismatch | 1 Quick Solution

vSAN cluster UUID mismatch Cause:

vSAN Cluster UUID mismatch will occur when we try to re-add a host which is part of an existing cluster. If you are trying to add a host which is built from scratch then UUID will not mismatch at all.

The Monitor –> Tasks should give more information as shown below.

vSAN new host UUID mismatch
vSAN new host UUID mismatch

How to resolve?

SSH to the ESXi host which we are trying to add. once login to the shell we need to leave the vsan by running below command with option and argument.

[root@pve3:~]
[root@pve3:~] esxcli vsan cluster leave
[root@pve3:~]

Verify from logs

Confirm the same from the logs.

[root@pve3:~] cat /var/log/*  | grep leave
2020-08-07T14:03:40.034Z info hostd[526561] [Originator@6876 sub=Vimsvc.TaskManager opID=esxcli-6a-673c user=root] Task Created : haTask--vim.EsxCLI.vsan.cluster.leave-3951224597
2020-08-07T14:03:40.034Z info hostd[526560] [Originator@6876 sub=Solo.VmwareCLI opID=esxcli-6a-673c user=root] Dispatch leave
2020-08-07T14:03:40.796Z info hostd[526560] [Originator@6876 sub=Libs opID=esxcli-6a-673c user=root] VsanIscsiTargetImpl: Handling cluster leave event.
2020-08-07T14:03:40.810Z info hostd[526560] [Originator@6876 sub=Libs opID=esxcli-6a-673c user=root] VsanIscsiTargetImpl: Handling cluster leave event completed.
2020-08-07T14:03:57.645Z info hostd[526560] [Originator@6876 sub=Solo.VmwareCLI opID=esxcli-6a-673c user=root] Dispatch leave done
2020-08-07T14:03:57.645Z info hostd[526560] [Originator@6876 sub=Vimsvc.TaskManager opID=esxcli-6a-673c user=root] Task Completed : haTask--vim.EsxCLI.vsan.cluster.leave-3951224597 Status success

That’s it, now once again try to add the node. It should work.

Conclusion

vSAN cluster UUID mismatch error will be thrown while we try to add a host to an existing cluster which is part of the cluster earlier. If you found this solution saved your time, subscribe to get more similar to this.