Adding additional licenses to ESX 3.5 / vCenter

Hi,

Just wanted to check the process for adding new licences to an ESX 3.5 / vCenter 2.5 environment.

Can I have multiple .lic files in the license folder? There is currently a license file in place, but there is a need to add a licence for a new server, purchased as a vsphere 5 licence which will need to be downgraded to an .lic file?

Is there any risk involved to existing hosts if there is a problem with the licensing server after adding the new file?

After adding the licence file, I guess I just need to configure the host to point to the license server. Should I do this before or after adding the host to vcenter?

thanks in advance.

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