Unused (Never Mounted) Tapes dissapear from Media tab.

[AlChie]

Greetings!

I have faced such issue:

Unused tapes have dissapeared from media tab. It is not a problem of Library as we have already done inventory and were able to find 600 tapes. In the time interval from inventory of these 600 tapes and dissapearance of unused tapes we have used 300 tapes at least once.

Time went on again and just recently we have recieved error 96 from one of our policies that used this robot.We looked at media tab and were very supprised to see only 300 full medias instead of 600. We made inventory once again, and it easly detected these 300 free media and put them back to fight.

But it was not the only robot which lost it's medias. We have 14 robot total and 4 more of these also lost free medias.As another example: we have 1 robot with 300 tapes and we didn't make it to use so it lost all 300 medias :) .

I would like to know wat might caused this data loss of inventory.

As I had understood: NBU doesn't do inventory by itself, so it doen't refresh the amount of avaliable media just by openening media tab. It queries the library and waits for barcodes to assign media to slots etc.

In that time interval  (between inventory and when we realised that everything is gone :))we had done the following: we restarted 3 libraries (1 is physical (Quantum) and 2 is VTL (DataDomain) and we alse did a restart of NBU master server.

What could have caused this?

Many Thanks,

[Amol_Nair]

If a tape is empty it can be easily removed using the vmdelete command line tool.. So you would need to check if there is any cron script or any 3rd party tool or script which could be checking and unknowingly removing empty tapes from nbu..

The script or tool if any may be attempting to remove all tapes but vmdelete command would fail if there is valid data on the tape and hence removing only empty tapes..

Also do check if for test purposes if anyone tried modifying nbu files..
I once had a customer who replaced the vminitlist file itself in their server in an attempt to create some custom reports and the end result was robotic inventory messing up and reporting unknown/ unheard of error messages..

Nbu would not delete medias automatically, but if the command is called there is nothing that would stop the deletion of the tape either if its not assigned..

Best bet would to enable logs and keep and see if we see commands running yo delete tapes and that would give you a timeslot to check with OS team to isolate for any 3rd party scripts or tools

[mph999]

I would agree with Amol.

I have never heard of NBU 'forgetting' about media like this.  The media is held in the NBU sql database (nbdb) - it can't accidently lose lines from the media table - it requires a specific SQL command to be run against the database to remove an entry.

If you had DB corruption, then yes, bad things could happen, but corruption is random and wouldn't target specific unsed media - and would almost certainly either cause the nbdb to fail to start/ run or cause some real bad error messages,