Migrating vSAN Cluster To A New vCenter VM That Is Hosted On The vSAN Cluster

[smittytech]

I understand this is a weird situation, but it is what is being asked of us.

We have 2 vSAN Clusters built using a vCenter that is hosted on another device, but meant for another environment. We created a new vCenter VM on one of the hosts located within the vSAN Cluster. We would like to migrate the vSAN Cluster to the new vCenter.

I've found guides on how to migrate vSAN's to new vCenter Appliance. The current hiccup is how to get the vCenter VM to stay on/active during the process.

What's my best option here?

1. The current thought is to build a separate host that has storage outside of the vSAN.

2. vMotion vCenter to it.

3. Migrate all the vSAN Cluster hosts.

4. Then disconnect the separate host from the old vCenter and connect it to the new vCenter (but as a separate datacenter). Then vMotion the vCenter VM over.

Is there a better way?

We sadly don't have a SAN and have limited space elsewhere.

Thanks!

(Sorry, the description section wasn't editable on my other computer, so I had to post without it originally)

Message was edited by: smittytech

[GreatWhiteTec]

Hi Smittytech,

Not quite following the logic here. Why wouldn't vCenter stay on/active during the process?

From a high level view the process is quite simple:

• vCenter A (source - OLD)
• vCenter B (destination - new)
• Create an empty vSAN enabled cluster in vCenter B
• Create (export/import) vDS on vCenter B
• Match SPBM from A to B
• Add vSAN hosts to vCenter B - new vSAN Cluster
  • No need to disconnect from A (automatic)
• Attach hosts to vDS PGs
• IF vSAN encryption is enabled - see my blog post https://greatwhitetec.com/2017/06/06/replacing-vcenter-with-vsan-encryption-enabled/
  • https://greatwhitetec.com/2017/06/06/replacing-vcenter-with-vsan-encryption-enabled/

The location of the new vCenter as far as storage goes should not matter much. VMware supports vCenter within vSAN.

Hope this helps

[smittytech]

Hey Great_White_Tec,

Thanks for the response. My original understanding was that it would transfer over without issue, but as soon as I started migrating the final host (with the vCenter VM), I lost all connectivity to it (couldn't even ping). I did wait awhile, but the connectivity never came back. I had to use the KVM console to reset the networking and reconnect it to the old vCenter before I could get back into it.

I have the whole cluster back on the original vCenter now, and it appears to be working fine there now, but is warning me that all hosts need to be put back into maintenance mode to be compliant.

---

I will try again though, as I did disconnect it from the old vCenter first (as the guides had instructed).

Thanks!

[GreatWhiteTec]

I see...  migrating the vCenter to the vSAN cluster before migrating the last host may do the trick here. Looks like you have the chicken and the egg scenario.

The final host has the new vCenter or old vCenter?

[smittytech]

Looks like you have the chicken and the egg scenario.

Correct. Pretty much the story of the whole build.

The final host has the new vCenter on it.

We had a problem with a spare C220. I'm going to wipe that on Monday. Add it to the old vCenter and vMotion the new vCenter to it. Rebuild/migrate the vSAN cluster over to the new vCenter, then add the C220 to that vCenter (not on the vSAN) and vMotion the VM over.

Unless there is a better way?

I'm fairly new to the sysadmin role so I'm sure there are plenty of things I am missing that could make this easier.

Thanks for the help!