Question about moving vCenter from one physical server to another

[rcustersp]

Here is the scenario:

We currently have vCenter 2.5 installed on a windows XP box. It is managing 3 ESX hosts in a HA cluster. I built a new server with windows 2008 x64 and installed vCenter 4.0 on it using a copy of our vCenter SQL database. Everything is great so far, but now I have to tell the 3 hosts where the new vCenter is. I have the procedure for changing the ip of the hosts. What I am wondering is when I go into the first host and change the ip to the new server, the old server will be missing one host. Won't it try to power up the vm's that were on that host on the other 2 right away? Same thing on the other end. Once vCenter 4.0 has one host added, won't it try and power up all of the vm's on it because of HA? Can I prevent this just by stopping the vCenter service on both servers before attempting the switch?

[Troy_Clavell]

Here's a good KB article that describes the process.

http://kb.vmware.com/kb/5850444

[rcustersp]

Hey Troy,

That is the document that I am following. My question pertains to what happens when you change the ip's on the hosts.

Thanks

[Troy_Clavell]

You are not changing the IP address of your ESX Hosts, you are just updating the IP address of your new vCenter Server

>Note: If the IP address of the new VirtualCenter Server has changed your ESX Servers must be made aware of that change, otherwise the ESX Servers continue to send their heartbeats to the original IP address of VirtualCenter and appear as Not Responding.

[rcustersp]

Right. When I change the ip address to the new 4.0 vcenter server, won't the current 2.5 vcenter say, "Hey, we just lost a host. We should probably power up those VM's on the other 2 hosts that still exist." Or will having the vcenter server service off prevent this?

[Troy_Clavell]

you can't have ESX being managed by two different vCenter instances. So, you need to disconnect and remove the Host(s) from your 2.5 instance and "add host" into your new vCenter4 instance. Doing that procedure will update the vpxa.cfg entry automatically.

[rcustersp]

Sorry for being such a pain. The hosts already exist in vcenter 4.0 because I used a copy of the database to set it up. All I need to do is tell the hosts to communicate with the new server and everything should be good. I just want to confirm that I wont have any issues with HA trying to move or restart virtual machines once I start the process of updating the vCenter IP on each host.

[Troy_Clavell · Accepted solution]

your VM's will be fine. All you are doing is updating the vCenter Management agents. So, you could simply do a disconnect and connect and the information will populate as well.