About ' Status Code 277: the drive is not ready or inoperable.':
Please ignore the links to Veritas drivers in the last TN (those links do not exist any longer).
Check that Vendor (IBM) drivers are installed.
I have two robots, one in locationA and one in locationB. Each have media servers that use them, BUT THEY DO NOT SHARE. So no media servers in locationB should use robotA.
Every now and then, when I recycle netbackup, the drives in robotB do not work, it says robot is not available.
When I go to mediaserverB and run tpconfig - I see the robotA AND robotB - if I delete robotA, and stop and restart netbackup, everything works fine.
Scan from OS - if sgscan tape or scan -tape show drives, then either tpautoconf -a or use the GUI wizard to rescan drives.
I have had occaision where some hardware work is done and the drive paths shuffle, and I actually have to delete and rescan the drives before they are working.
Check the Media and Device Management, Devices, Drive and filter for contains "missing" - see if drive path is missing.
I use acsls and only the media server controlling the robot show enabled. The others all show NO.
On my data domain VTL, they are all YES