Hi,
I don't think that is possible. If you have a (licensed) VC server, the only way to add an eval node is by putting VC into eval mode as well. Problem is that your VC install is propably older than 60 days, so that will not work either.
The ony way to solve this (as far as I know) is to reinstall VC into eval mode as well... You propably should license the ESX server with a host license then. In turn that adds a problem when you want to test vmotion, because that is not possible with host-based licenses....
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