This weekend I had an issue with a backup failing on a client using LAN-Free. When checking the TSM actlog the error I kept seeing was:
ANR9999D (Session: 265500, Origin: OD0BG-UAX001-STA) mmsshr.c(3874): ThreadId<13> Unable to obtain model type for '/dev/rmt23', rc = 46(SESSION: 265500)
So I had a good idea that the client and TSM Storage Agent were having issues communicating. I knew this because I had seen this error before when the TSM client and TSM Storage Agent were not at the same release levels. Checking the TSM client I found it at 188.8.131.52 and the Storage Agent at 184.108.40.206. Turns out an admin upgraded the client without knowledge of the Storage Agent, causing the backup failures. This is an example of what can happen when someone tries elbow their way into another groups area without the knowledge to do it right.