Upgrade VCenter to New Server

[msassman1]

We are upgrading VCenter server 4 to 4.1 and are installing 4.1 clean on another machine. When we Move the first Host to the New server (Remove from existing and then add on the new), we are prompted that it is licensed on another VCenter installation. We want to move the first Host over and test, but need to use the same license that is on our existing production VCeneter server. Does anyone know if there is a grace period that will allow us to move the first machine over to the New server, and then allow us to move the 2 other machines over a few days later without the later machines having any issue or down time?

[Troy_Clavell]

you can run vCenter in evaluation mode for 60 days.  When the migration is complete you can plugin the permanent license key.  You will however, have to bring over the license keys for your ESX/ESXi Hosts.

[msassman1]

It askes for the license key when adding the VM host, so eval is greyed out due to the host being prior licensed on the current machine. 

[Troy_Clavell]

you can plug in the ESX/ESXi licensing key into your new vCenter Server. Go to Home--Licensing--Manage vSphere Licenses. There you can enter the key.  Or, since ESX/ESXi can only be managed by one vCenter, just plug in your production key when you "add host"

[msassman1]

We will still have the 2 other production hosts running on the current VCenter server. Will they still function if the license is entered on the new server, and if so, how long is the grace period.

[Troy_Clavell]

yes, they will still function.  I assume you are using a combined license key (all licenses are in a single key). This is an acceptable procedure as you migrate off one instance to the other.

Since an ESX/ESXi Host can only be managed by 1 vCenter, all your doing is shifting license files around.  The other hosts that reside in the old vCenter Server will continue to function as normal.

The only thing you lose is historical data because the new host is being managed by a new vCenter and DB.

[msassman1]

Thank you.

[VirtualSingh]

Just to share,  when you add an ESX host to the vCenter inventory, it installs agent and etc from the new vCenter. So in your case if you detach one host from production vCenter and add to new vCenter inventory, the host will get new vCenter agents and etc; therefore no conflicts running both vCenter parallel.

Troy has described very well.

I hope things will work for you!