Can the "previous volume pool" field be modified?

[Darren_Dunham]

I have a standard Scratch pool that is populating all my normal volume pools.  So when a volume expires, it returns to the Scratch pool.

I have a small number of tapes that I would like to have special handling.  When they expire, I want them to go to a specific volume pool that is not Scratch, so they don't get tossed somewhere else.

I suppose I could code a script and run it every 10 minutes and it would probably catch the tape while it still lives in Scratch, but that's a lot of work and not a guarantee.  I'd prefer to be able to modify the "previous volume pool" field and have it go there automatically on expiration.  Is that possible?

Thanks!

[Nicolai · Accepted solution]

I am afraid that not possible.

• You can choose tape to return to a scratch pool
• Or to remain in a volume pool they belong. Free media will be allocated withing the volume, else a status 96 will be returned (this really not recommended)

Previous volume pool is information field and can't be edited. So I seems scripting is the only option.

Can you explain why you want to handle a small number of media special  - maybe there is a workaround from someone in the community.

[Will_Restore]

deja vu, see this thread:

https://www-secure.symantec.com/connect/forums/changeing-previous-pool-name-using-command-line

[StefanosM]

What you can do is to move all empty  "special handling"  tapes to their backup pool so when the tape is expired it will not go  to the scratch and create a script that check for these tapes and move them to a specific volume pool.

Netbackup when start using scratch pool was not moving the tapes back to scratch. You can use google to find one of the home made scripts that moves tapes to scratch and change it to do what you want.

One step more, disable the return to scratch pool and use the script to do all the work.

use cron or scheduler to run the script every 15 min.

[Darren_Dunham]

What you can do is to move all empty  "special handling"  tapes to their backup pool so when the tape is expired it will not go  to the scratch and create a script that check for these tapes and move them to a specific volume pool.

The problem is that the tapes are already in use, so I don't believe that I can change their pool until after they expire.

I suppose I could just freeze them so that they are not automatically reclaimed.  Easy enough to handle in a script.  Just trying to avoid that. 

[Darren_Dunham]

Can you explain why you want to handle a small number of media special  - maybe there is a workaround from someone in the community.

I want to take media that are above a certain number of mounts and move them to a pool that will be used for longer-term retention.  So before it exceeds my threshold of mounts it is moved to a pool that will see less use.

[StefanosM]

yes, this is somthing you have to do tape by tepa as they expire. freezing is a good idea. But keep a track of the manualy freezed tapes.

[Ankit_Maheshwar]

There are few rules.

1- Can’t move assigned media to any other volume pool.

2- Can’t change any rule in existing volume pool.

3- Can define scratch rule while creating volume pool.

4- Can’t freeze or suspend unassigned media. Netbackup itself can freeze the media.

5-Can move media owner for assigned media by Move option.

6-can’t move freeze media on any other volume pool. First media need to unfreeze.

7- Media controlled by different robot type can exist in same volume pool but can’t in same volume group…

Script can work for media movement  to a specific volume pool. But media should not be frozen.

[Nicolai]

Is it worth the effort ?

Just a example:

Minimum retention at our site: 1 month

Media density in use before beeing deprecated : 3.5 years

Maximum usage count :  3.5*12 =  42 times.

So after 3.5 years of usage the tape hasn't been used more than 42 times - there is still plenty of room to the theoretical 1 million passes* the specifications says.

http://docs.oracle.com/cd/E21419_03/en/LTO5_Vol4_E4/LTO5_Vol4_E4.pdf

* writing from start to end of tape consist of more passes. See recording layout in the link above

[Darren_Dunham]

Sometimes, yes it is.  Equipment fails, things break, etc..

# vmquery -b -rn 0 | awk '{print $8}' | sort -n | tail 

531

536

567

633

854

870

1416

2384

2397

2435

[Nicolai]

Mount and full writes are not the same. You may need to mount a tape many times to fill it up.

Seen from media reliability side this does'n count.