ESXi boot disk replacement - will this mess up Veeam?

[lunadesign]

The USB boot disk on my ESXi 6.5 server is failing.

Cloning the boot drive does not look possible. It looks like I may need to reinstall to a new USB boot disk (or possibly a local SSD) and then restore the host configuration using the info in VMware KB 2042141 (https://kb.vmware.com/s/article/2042141). That article mentions that I'll have to re-register the VMs after the host config is restored.

Will this mess up my existing Veeam backups? (I'm currently on B&R 9.5 U4.) IE, will it think these are all brand new VMs? Is there any way around this?

Thanks!

[rennerstefan]

Hi,

if you work with a single host and you re-register the VMs it will result in a new MoRef ID and the job will perform full backup as for us it is like a new VM.
If you have a Vcenter and at least one more host you can perform a vmotion the MoRef ID in Vcenter will remain the same and no new backup would be created.

So it’s a little depending on your environment.
One more thing, I’d recommend using a local disk for the new vsphere installation as USB and SDCards are more likely to cause problems.

Thanks

[lunadesign]

Thanks for the quick response rennerstefan! What happens if I am using vCenter (VCSA) with only one host?

Note: It's unclear to me if replacing the boot disk requires me to (1) re-register the VMs or (2) connect vCenter with the updated host...

[rennerstefan]

Replacing the boot disk will mean you have to reinstall the vsphere OS. And with that it is a “new” host, also if it is the only host in a Vcenter. You already wrote that cloning the boot disk is not possible so it will be a new installation.
Only if you already have the host in a Vcenter and Veeam jobs use the Vcenter as source for backup it would be possible to migrate VMs to a temporary host and maintain the MoRef IDs.
As far as I understand from you, you only have the host added to Veeam now. So once you reinstall the Host with the new OS on the new boot media you will need to re-register the VMs and with that they will get a new MoRef ID.
You could open a support ticket at VMware to get assistance from them on how to replace the boot device while maintaining the MoRef IDs.
Sorry to have no better answer but in this case options are limited.

[Andreas Neufert]

If you have added the Vcenter to veeam and only have one VMware host, maybe temporarily install another host and vmotion/storage vmotion the VMs while they are running. This will keep the moref ID. Update the host and transport the VMs back.

If you have licensed the host with socket licensed, you have to revoke the license after the update or the vmotion to the temporary host, to free up the license and let Veeam consume it with the new/recreated host.

[lunadesign]

Thanks Stefan & Andreas!

I'm on a vSphere Essentials Kit license so vMotion unfortunately isn't an option for me. In case it helps, my current Veeam B&R license is a per-socket license (maintenance expires soon so I may move to VUL).

FWIW, I set up a quick test with 1 host and 1 VCSA VM (both in eval mode) plus a test CentOS VM. This test differs from my production environment in that it has no Veeam and the datastore is on a local drive instead of accessed via iSCSI. And it obviously has a lot less VMs.

Before using the ESXi ISO to reinstall to a new boot drive, I wrote down the host UUID and VM MoRef IDs. After I reinstalled ESXi, the newly installed host didn't show either VM. No surprise there.

However, once I restored the host config, the VMs were there and they still had the same MoRef IDs as before. No re-registration of VMs was needed. The host UUID also was the same as before. vCenter seems to work just like before the host reinstall.

Does this mean that in my production config, Veeam will continue to recognize the VMs as before? (IE, it won't think the VMs are new?)

[rennerstefan]

Hi

at least I haven’t tried yet the host configuration backup for it. Based on what you wrote it seems they IDs are maintained in this case.

What I would try is to do the same test again with the test host and test vm but also include a test Veeam job with it so you can see if it works.

As said I can’t guarantee as I don’t have all details on what VMware stores in the host configuration backup of esxi at the moment.

To be sure you may also want to open a case at VMware and ask the ID questions. They should be easily able to assist you here.

[lunadesign]

Stefan - That's a great idea. I'm nervous about messing up my production Veeam setup so I've requested a temporary/eval license from Veeam for my current (older) B&R version so I can "practice" with a temporary Veeam install. I'll keep you posted!