Forum Discussion
There seems to be some communication issues here too - mention of unexpected message from NDMP and a lot of name resolution going on - which seems to resolve host hames as IP addresses rather than names.
Worth making sure you Master and Media Servers can reolve each other and the filer by short and FQDN name - use hosts files if neccesary.
Odd to have robot / tape errors on a VTL so most likely a communications / configuration issue.
Run through you config again and to be sure of everything and ask the NDMP admin for the messages log from the filer to see if that is showing any errors - also make sure that the fibre switches involved are not showing any issues (some switches will cause a port reset if any error is detected which can disconect drives)
Finally take a look at the event log on the VTL to see if that is reporting anything
This may all be a communications or connection issue, but if it centres around the NDMP then that is where you need to look
Hope this helps