How to deploy vSan witness

[jim77]

Greetings; I'm attempting to setup vSan (v7.0.2) on a 2 host setup (ESX 7.0.2). Using the QuickStart feature. ESX1 hosts vSphere client; VCS.

Have a few different problems:

1. The instructions say to deploy the witness appliance in a different cluster from the vSan cluster however; both ESX hosts are in the vSAN cluster - how can I deploy the witness appliance in a different cluster when it has no ESX hosts (they're in the vSan cluster)?

2. If I deploy the witness on ESX2 I have to turn the witness off so I can put ESX2 in maintenance mode in order to run Quickstart. With witness off, I cannot complete Quickstart through step 3 Configure cluster. If I leave ESX2 out of maintenance mode to keep witness running Quickstart step 2 shows an error under "all required hosts are in maintenance mode" and I cannot get to Quickstart step 3.

3. If I deploy the witness on ESX1 I get a message: "Host esxat003gum0001.anzguam.com running workloads other than VCSA alone or with PSC while undergoing HCI configuration is not supported" and I cannot find any reference to figure that out. What am I missing to setup a 2-node vSan cluster?

[TheBobkin]

@jim77 The Witness should not be running as a VM on a host in the cluster it is Witness to - that is unsupported and can result in a number of serious issues and the data wouldn't really act like normal FTT=1.

The Witness should be added to vCenter inventory as a standalone host or a different vSphere cluster by itself, it should not be added as a host to the cluster with the other nodes and shouldn't be processed using Quickstart.

If this is a homelab and you don't care about reliability/redundancy here then just configure the cluster without Quickstart. If this is a real environment expected to run workloads then stop and re-assess what you are doing here.

[IRIX201110141]

A 2-node cluster is in real a 2+1 where the one is a virtual ESXi which save a license and needs to be placed in the cloud, or  in a HQ when youre a robo or in another cluster or stand alone host in your environment.

Regards,
Joerg

[jim77]

Thank you for your response. That's my issue. How to deploy the vSan witness into as a standalone host. I have 2 ESX servers and attempting to deploy from either one results in the witness appliance being part of the vSan cluster or not deployable.

How do I deploy the witness as standalone?

[IRIX201110141]

"ON" a standalone host not "as".

You need an extra ESXi (free version will work) or deploy the witness in the cloud.

Regards,
Joerg

[jim77]

thanks... Since the ESXi host is only supporting the witness server, it can be a fairly light server, correct? Would a workstation/desktop work?

[IRIX201110141 · Accepted solution]

If you can install ESXi it give it a try.

[jim77]

Thank you! I'll revert if I have any difficulties with this. But it really makes sense and explains a lot. I think they need to a bit better job explaining that you'll need a 3rd ESXi server to deploy the witness--but maybe that's obvious to you experienced folks... 🙂

[IRIX201110141]

Well.... this very special 2-node setup comes way later and it starts with 3-node as minimum.

We pray for god that every customer agree to start with 4 nodes and not the bare minimum of 3. Reason is that we are like to able to do a full data evacuation when a host went into maintenance mode.

Regards,
Joerg