I have 2 ts servers set up in a farm with load balancing, session broker and round robin DNS.
This has been working fine for 2 years, if users don't log off properly, they are re-routed to their disconnected session when they try and reconnect.
Some users have now been migrated to new workstations on a different network (different IP range) and new domain. No change on the servers, and the users are still logging into the terminal server farm using the same credentials as before (so no change)
Somehow these migrated users are now ending up with a disconnected session on one server, and an active session on the other.
The servers have always been set to "restrict each user to a single session" and up until now it has worked without a problem.
There is a one way domain trust in place, with DNS forwarding, however I don't believe that this should be causing problems, as the users are able to connect and authenticate to the terminal server farm without any problems. These users are not local to me, and I've tried to reproduce the scenario at my desk (on a machine in the new domain) without any luck.
Any ideas? I don't even think this scenario should be possible from a technical point of view.....