Hi Matt,
We have had some creative cases regarding this before. KServer.exe especially checks the following in determining if it should create a new account (new GUID) or check into an existing Agent (GUID) for an agent:
- Agent displayName (Machine ID + Group + Org)
- MAC Address
The displayName item is easy to provision for, however it is the MAC address item that is of more concern - I am not sure if any non-persistant VM setup allows for static MAC addresses to be assigned to a pool of VM's to create (or even a MAC Address reservation, like a DHCP reservation, etc...), so if that has to be the case, then every time the new VM appears and regardless of how the agent is installed, a new GUID would be created for said machine, and then you would begin to have hyphenated (ie.: name.group.org, name-1.group.org, name-2.group.org, etc...) entries appear in your VSA. Each one of these records are counted as an occupied agent license with any status until deleted and purged from the VSA, so that will occupy additional licensing seats until removed. We had a customer experience this MAC Address issue and they had no way around it, so they scripted deletion of the offline entries via http://www.autoitscript.com/site/autoit/ - kind of a band-aid to the issue, but this is what had to be done with those particular clients in those non-persistant VM scenarios.
Also, with this said, Kaseya Engineering is well aware of how non-persistant VM's are becoming more of a routine reality in today's scope of IT operations. They are aware of this concern & resulting VSA Agent issue and are exploring ways to try to manage this without disrupting the normal Agent management flow as well. Feel free to submit a feature request ticket requesting supported non-persistant VM and Agent management adoption as well for sure if you would like (the more the merrier! 
).
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 | Dylan M. Lagi / T3: Senior Support Specialist | Kaseya Support / http://www.kaseya.com/support |