We tried using vpn to connect to FMS, due to we moved a fileserver inside the firewall so we needed to be able to access that over vpn. When sending snapshot links over email and the user clicking the link, it first appears fine, but if you try and search, only the same posts will be seen. After a while we had "empty posts" and when erasing them other posts were blanked out, missing all data – even autogenerated and locked data. It still took us half Friday and half Monday to see it is really a crash and a very long Monday evening to understand what was the reason.
It appears that the same user is connected both over the vpn and a normal connection (from the snapshot link) and the result was the worst crash we've had since the early 1990's. We had to stop and go back to the last backup before we moved to vpn.
Will not use VPN for FM again, but that is the way I reach the servers – including the one that hosts FMS – so now I'm nervous that I might find myself having FM open when checking on the server and clicking a snapshot link in an incoming email. Maybe that is ok, as I have done this many times before, but it would only appear if I open FM when I have connected to the servers VPN and then get the email with the snapshot link. Anyway, this is a serious risk.
We're on FM/FMA/FMS 16 on OS X 10.12.6.