I just asked this question to VMware not to long ago. Here was there answer as it relates to VDM 2.1
"There is no specific restriction on the max amt of guests
VDM can support.
VDM is mostly involved in channeling connections, so its
load is considerably less that VCMS. We test each VDM at 1000 concurrent
connections (doesn't mean the 1001th connection will fail) and you can have
multiple VDMs in tandem (we test upto 5) to scale higher."
Hope this helps
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The current release, VDM 2.1 (aka Monza) has been tested to 1500 SSL-tunnelled users, and more if using a direct, non-SSL connection.
