Netbackup make tape drives to go down

[jayram07]

HI,

Would like to know why netbackup keep my drives down when it founds the WRITE PROTECTED media. We have several other non write protetced medias available in the libray but it's not using it.

Error write error on media id HFE082, drive index 6, writing header block, 19
Error TapeAlert Code: 0x09, Type: Critical, Flag: WRITE PROTECT, from drive ukyorm0015_000_TLD_2 (index 6), Media Id HFE082
Error write error on media id HFE081, drive index 3, writing header block, 19
Error TapeAlert Code: 0x09, Type: Critical, Flag: WRITE PROTECT, from drive ukyorm0015_000_TLD_3 (index 3), Media Id HFE081
Error write error on media id HFE081, drive index 3, writing header block, 19
Error TapeAlert Code: 0x09, Type: Critical, Flag: WRITE PROTECT, from drive ukyorm0015_000_TLD_3 (index 3), Media Id HFE081
 

All my 2 drives went down after this error, why can't it go ahead and use the good medias?

[Marianne · Accepted solution]

Question - why are there write protected media in backup pools or in Scratch?
NBU has no idea that they are write protected and will only know when the I/O error is received from the tape driver.

If there is good reason why they should be write protected, move them to a different, non-backup pool. Ensure that you have only writable media in backup pools or in Scratch.

Each attempt to write to these tapes were logged as an I/O error.
3 I/O errors on a tape drive in a 12 hour period will cause a drive to be DOWN'ed.

See this TN: http://www.symantec.com/docs/TECH9748

DOCUMENTATION: How Symantec NetBackup determines if a tape should be frozen or the status of a tape drive should be changed to down, and how to change this behavior

[sksujeet]

There is a technote which explains how medias are assigned in the NBU, there is lot of logic and explanation behind the scenes. After certain tape alerts NBU makes the drive down and that is normal. As you already aware that it is causing due to write protected tapes it is better to take these tapes out of the library. The other way you could get rid of this is by suspending or freezing the media.

Edit: Oops Marianned already explained it very well

[jayram07]

Media's were actually loaded for restore purpose, will move them to different volume pool.

[Marianne]

You will not be able to move them to different pool as long as they are Assigned.

Best to suspend them as per sazz's advice.
NBU will not try to use suspended media for backups.