Replication during upgrades

[pkelly_sts]

We've recently purchased licenses to cover backups at a remote site (which has been scarily devoid of backups for far too long) and the site is essentially a two-host setup (VC-connected) with only internal (no shared) storage with 4 VMs running on one host and the other effectively sitting as a standby.

Thing is, these hosts are also ESXi 4.1 so well out of date & needing upgrades. Now that we've got Veeam available there and have successfully completed an initial replica from one host to the other, I was wondering if we'd be able to leverage these replicas to allow us to upgrade one host at a time.

In other words, if we "fail over" all VMs to host 2, in-place upgrade host 1 ESXi, will we then be able to fail them back to host 1 to enable us to do an in-place upgrade of host 2, or will the different ESXi versions cause us issues?

Just thinking aloud through upgrade options at this point & thought I'd double-check what's feasible as we've never needed to fail-over in anger yet, only tests/sandboxing etc.

Paul

[veremin]

In other words, if we "fail over" all VMs to host 2, in-place upgrade host 1 ESXi, will we then be able to fail them back to host 1 to enable us to do an in-place upgrade of host 2, or will the different ESXi versions cause us issues?

Since it's going to be in-place upgrade, the described approach should work smoothly. Though, I would backup those VMs first just to be on the safe side. Thanks.

[pkelly_sts]

Excellent, I suspected as much, thanks for the confirmation.

(Backups are very high on the agenda now!

[veremin]

You're welcome. Kindly, keep us updated on the results of your findings. Thanks.

[Delo123]

Hi Paul,

you should be fine doing that. However remember that if you should update the virtual Hardware on the vm's (which is not necessary) beyond vmx-7 or 8 i believe you cannot run them on esx4 anymore.
So simply update one host, move your replica's over, update the other one and then you can do everything you want

[pkelly_sts]

Yup, I'm aware of that but it's certainly worth highlighting here to others' that might try the approach. I'll report back when we're done...