AIX

I am having my 14 Aix 5.3 servers on bladecenters connected with my Tape Library.
I had a backup scheduled on tape library but after taking backup successfully,
Now,

Question 1:-
I wanted to restore backup but tape library could not recognize the tape and I get I/O error in TSM. I think it is not recognizing the barcode Label on tape though I think it just check in the tape blindly while backup starts. Whats your suggestion on this any solution..?

Question 2:-
Due to above issue I removed my tape drive rmt0 from TSM Server using command

#rmdev –dl rmt0

After that I wanted to reconfigure my tape library so I fired
#cfgmgr
But it does not detects my tape library rmt0
Then I restarted my tape library and issued same commands but same result
#lsdev –Cc tape
does not throw any output
Also in /dev/, rmt0 directory is absent
What can I do to reactivate my tape drives other than rebooting my server (Aix 5.3)?

Please help immediately, thanks in advance.