So this is second part of the 2 node stretched vSAN cluster upgrade. You can find art 1 here, which is mostly perquisites and links to the upgrade of vCenter.
As mentioned previously you need to first upgrade the vCenter, then the second part is to replace the the vSAN witness node, which is what we will be doing here. If you haven’t done the vCenter yet, you can find the prerequisites for this here and the upgrade itself process here.
Replacing a witness node could perhaps sound a bit dangerous but really it is not. It is the preferred way to go with upgrading a vSAN today and it is as easy as deploying an ova from customer connect and then after deployment go to the vSAN stretched cluster configuration page and select replace node.
Below is the step by step guide:
Go to your vCenter and select to deploy an OVA, select the witness ova that you downloaded above.
Next you enter the required settings, first location:
Then review the details:
Next we select the sizing, in my case I have very few vms due to a nested lab:
Select the storage where you want to put the witness host:
Next we select the networks for the witness host: and select the static IP.
Then it is time for the custom settings, make sure you get them all. This makes the witness deployment quite simple.
Supply root password and select the nic for the vSAN traffic.
After this click on Finish to deploy the ova template.
That completes the first part of the Witness setup. It has become a lot nicer since the 6.6 days with the deployment.
After this step is completed you need to add the new witness in the vCenter. This is done by simply just adding a new esxi Host. It is suggested to put the new Witness VM at the top most layer to avoid some warnings that may appear.
Verify that all is as expected when you import the vSAN witness:
Once the witness host is inside the cluster you can go to the vSAN cluster and find configure and then the Fault domain part:
Previously you had to disable the stretched cluster and set it up again with a new witness. This has changed in 7.0. Now you can simply replace the witness by selecting “change Witness host like above.
You then get a guide that lets you select the new witness:
Once selected you click next, select the disk groups for the witness host:
Then you click next and then finish and the witness host replacement takes place:
Once all the configuration steps are done …
you should see the configuration with the new witness host:
And then as final steps you can now shutdown the original witness host and then remove the witness host from vCenter and then the vm itself also, leaving you with only the new Witness host.
That takes care of the Witness, next is the rest of the upgrade.