Can be NBU configured to use tapes in secuencial order on tape pools?

[rbadilla]

Hi people:

We are helping out a final customer who is coming from HPE DataProtector 9x.  They were using a one drive LTO5  library.  They take as workflow using tapes in sequential order without code bars, just written label to take control of the contents of backups.

Now they are using a 4 LTO9 drives HPE StoreEver MSL3040 (firmware 3320), with primary server a HPE Proliant DL360 Gen 10 server with Windows 2022 and NBU 10.3. Several pools were made and at least 4 tapes are assigned to each pool.

But following the current way to work, they want that NBU uses the tapes on all pools in sequential order. For example, PBX pool has tapes label: 

0017L9 000017L9 HCART3
0018L9 000018L9 HCART3
0019L9 000019L9 HCART3
0020L9 000020L9 HCART3

When NBU run backups using that pool:  use first tape 0017L9 if fills up then 18L9...  and so on.

if CDRS pool  has tapes: 

0037L9 000037L9 HCART3
0038L9 000038L9 HCART3
0039L9 000039L9 HCART3
0040L9 000040L9 HCART3

When NBU runs bkps using that pool, first use tape 0037L9, when fills up 0038L9 and so on.

There are few backups made since the solution is very new. But the first trial backup took tape 0020L9 instead of the 0017L9..  the option to leave tapes out-library is off-topic since the DataCenter isn't near the office and have just security people who can't access the library except from programmed visits to load the 40 tapes library.

The other option will be to leave the pool with just one tape but if fills will use the next in order (sequential) o just any tape.

They are very comfortable with the control used to have on DP and how backups were made. So they want to fit NBU to their needs as far as possible.

Any ideas if this sequential order on pools is possible, o how?

[StefanosM]

As this is difficult to achieve, how many load ports/mail slots the library has?
you can export the tapes, almost automatically, using the load port of the library.

[rbadilla]

Hi StefanosM, thanks by take time to read and try to seek advice.

I will dig around the docs of the library HPE StoreEver MSL3040 about that number... and tell you.

[StefanosM]

MSL3040 has 5 mail slots per module. So, for one 40 tapes module, you can ask netbackup to move 5 tapes to mail slot per eject command.
Then the data center security people can remove them from the library. If you have more that 5 tapes to eject, you can repeat the procedure.

The hard way to solve your problem is to use scripting.
move a tape to the desired volume pool. Left all other tapes to netbackup pool.
create a script to check every 10 minutes if there is a tape with no "assign date" in the pool.
if there is, then netbackup hasn't use it yet.
if there is no tape, move the next tape to the pool.

You have to manually move the expired tapes back to netbackup pool.

[rbadilla]

Hi StefanosM, according to the docs there are maximum 5 slot for mailslots by base unit/expansion unit.

In the meanwhile, I just let one tape per pool. Also was thinking to make custom label and make rules, but feel that will not address the requirement in the former way. 

Is the tape choosing (algorithm) from the Netbackup pool publicly known ?

[quebek]

Hi

I am just wondering why this customer can't make use of the scratch pool. Please spend sometime to read about this in here https://www.veritas.com/support/en_US/doc/18716246-142505646-0/v95652367-142505646

and possibly advice this to the customer.

[Nicolai]

Netbackup has never been designed to use specific set of tapes in a specific order. You can semi make it work, but the best way is let NBU manage the tapes.

You don't need to know what backup are on what tapes. Netbackup catalog has all the information needed. They need to trust the Netbackup catalogue.

Some general advice :

• use a scratch pool
• use barcodes - as you really should use barcodes.
• Limit the number of tape pool and retention - it's a limited resource.

[mph999]

Yes, the way NetBackup selects media is publicly known, it's in the admin guide.

https://www.veritas.com/content/support/en_US/doc/24437881-136359134-0/v12948730-136359134

NetBackup is NOT designed to 'micromanage' media - it is an Enterprise product.

Although NetBackup is now very complex, lets go back to it's earlier days because they way it handles tape has not really changed, what was NetBackup designed to do ...

Create a jobid
Maintain a catalog of what is backed up and where

It was designed to have 'a load of media thrown at it' and then to let it worry about how that is managed.

It is impossible to configure NetBackup to guarantee to use media in a sequential order, it was not designed to do this.