In part 1, and in the comments, we briefly touched on some of the advanced bits of the XenDesktop licensing. Here’s some more detailed info:
Licenses are assigned for a 90-day period, as defined by “LP=90” in the license file. This means licenses are released after 90 consecutive days of inactivity. NOTE: If you have multiple farms and want license sharing, all farms must point to the same license server. There is no communication between license servers! As mentioned by 3 in the comments of part 1, you can release licenses prior to the 90-day timeout. To release licenses prior to the 90 days, use the command-line utility UDADMIN.exe. This is located in \Program Files (x86)\Citrix\Licensing\LS, and you MUST run it locally on the license server. More info, including switches and syntax: http://support.citrix.com/proddocs/topic/licensing-119/lic-admin-cmds-list-deletes-user-device-r.html
There is a 30-day free trial option (requires license server 11.9 or higher). If, after 30 days, you decide you like it, all you need to do is purchase and download a license file to move the evaluation version into production.
For you PowerShell nerds, there are also some PowerShell cmdlets available for v11.9 and 11.10:
Still haven’t gotten enough of XD licensing? Every question you could possibly think of has most likely already been addressed here: http://support.citrix.com/article/CTX128013 Take a look if you are having trouble sleeping. Me? I’m not. I just passed XenServer 5.6 today, and I’m beat.