We have SQL Server 2008 R2 Standard edition on our 2 Node Cluster.
I am planning to upgrade the edition to Enterprise Edition via the GUI.
There is an option under maintenance to do the edition upgrade.
It allows to upgrade the edition one instance at a time.

The question is do I need to do this on both the nodes like when you install a Cumilative fix and you can do a rolling upgrade ?

I upgraded the edition for all 4 instance on node 1. I kept them on node 1 during the upgrade as this is just my DEV environment. After moving all the instances to node 2 after upgrade, when I bring up the maintenance option, it shows all the instances are already Enterprise Edition, but it still allows the Edition Upgrade to go thru, which is very strange !!

Can someone share their experience on this ??