One odd day while working on a vSAN Infrastructure we might decide to remove the Witness Host which is already configured from the vCenter Server.
Just kidding! Not Really!!
In some scenario where you need to re-install the Witness Host you make think that it will be a good idea to just remove the existing witness host and install a new one without properly clean it up.
Ideally the Recommended way to perform the Cleanup is by Going into the vSAN Cluster > Configure > Fault Domain >Disable Stretched Cluster (Incase if you don’t have any Extra witness) or Change Witness Host (Incase if you have a spare witness host)
However, incase if you didn’t follow the steps and forcefully remove the Witness Host from the vCenter Server you might end up in the Below Issue.
Issue:
While Changing the Witness you will get the below Error: “Witness host already configured in stretched cluster”
Incase if you are seeing this issue, you will not see any option to disable the Stretched Cluster as well.
Solution:
(Note: If unknowledgeable on how to use RVC or are not comfortable with doing so, please open up an SR with vSAN Support)
- Log into RVC via vCenter SSH.
- Open vCenter SSH.
- Log into shell
- Run the command:
rvc - Login with
administrator@<domain>@localhost
- cd into localhost > datacenter > computers >vSAN Cluster
Once in the RVC console navigate to the cluster and use the following command:
vsan.stretchedcluster.witness_info .
You should see the witness that vSAN thinks should be in the cluster.
You can then remove that witness via the following command:
vsan.stretchedcluster.remove_witness .
