Mixed environment, vCenter 2.5 and vCenter 4.1

[shanfont]

Can I have a mixed environment during my upgrade/new install from ESX 3.5 to ESXi 4.1? I had to install vCenter 4.1 on a new server because vCenter 2.5 is not on 64-bit hardware. So I currently have a new vCenter 4.1 server configured and ready to add my host to the new vCenter. First I need to update those host from ESX 3.5 to ESXi 4.1. My plan is to do a clean install on my host. During this update I will have at some point a few servers on 3.5 and some updated to 4.1. Will I still be able to manage those that are on 2.5? I don't see why not.

[Troy_Clavell]

you can have a mixed environment, however, you cannot manage the same hosts in two different vCenter instances. Also, the two vCenter instances can't share the same DB instance.

Finally, vCenter 4.1 can manage VI3 and vSphere4.x Hosts, while vCenter 2.5 can only manage 3.x Hosts.

[nandogdc65]

Guys, I am in the middle of and upgrade. My current enviromnent is a virtual center 2.5 and EXS 3.5. I want upgrade to 4.1. As 4.1 has to be installed in a 64 Bit OS I will have to use a virtual server created in the 3.5 enviromnent to install vCenter 4.1. Would this be a problem?

I will be using this process to do the migration:

http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=102213...

Also how do I move the information form the license server that is was installed in the virtual center 2.5 into my new vCenter 4.1?

Your help is apresiated

Nando

[zsiga09]

Hi Nando,

I have the exact same environment and the same problem. Did you manage to migrate your licensing server to the new vcenter?

Thanks,

Peter

[Ather_Beg]

Hi zsiga09,

If you want to keep your new 4.1 environment clean, then I'd suggest keeping your old license server (generally the old VirtualCenter server itself) running for the duration of coexistance. The new vCenter server can talk to the old server and connects to port 27000 on the old server. Once all ESX servers are upgraded, you can remove that link from vCenter server settings.

Have a look at the full process that I followed for vSphere 4 Update 1 (the first link is more about introduction and pre-requisites really):

http://atherbeg.wordpress.com/2010/05/06/how-to-upgrade-from-vi-3-5-to-vsphere-4-with-x64-vcenter-se...

http://atherbeg.wordpress.com/2010/05/07/how-to-upgrade-from-vi-3-5-to-vsphere-4-with-x64-vcenter-se... &

http://atherbeg.wordpress.com/2010/05/09/how-to-upgrade-from-vi-3-5-to-vsphere-4-with-x64-vcenter-se...

You can follow the same process/sequence for vCenter 4.1. The only difference I can think of is that your ODBC DSN will be 64-bit (i.e. the normal one). The one for Update Manager remains 32-bit (although I haven't confirmed that yet). Please note: I upgraded ESXs using the manual method so that I can control partitioning. You can use a method that suits you. The process also covers licensing while coexisting and removal towards the end.

Hope this helps!

[zsiga09]

These articles are awesome, exatly what I needed. The project dropped on the priority list for a bit, but I'll get back to it soon.

Thanks a lot,

Peter

[zsiga09]

I'm done with the migration. Reading a lot and following recommendations from Ather Beg and others, I think the easiest path is this:

• Build the new vCenter 4.1 server
• Set licensing server for 3.5 hosts to be your old licensing server (You'll only need this if you're keeping some hosts at 3.5. 4.x don't use license server any more and you have the 2 months eval period to upgrade everything.)
• Rebuild the clusters
• Disable HA on old cluster
• Disconnect first then Remove your hosts from old vCenter so you don't have to go maintenance mode (and occur outage)
• Add hosts to newly created clusters
• Use VUM to upgrade them with the imported ESX 4.1 iso
• Set the new license key for the hosts
• Enable HA

Done