one duplication job is running at one time

[gurminder_singh]

Hello Guys,

We are facing backup issue due the duplication job.

in our environment we have set backup will first write on disk and then from disk to tape. And in SLP it has been configured that backup will be expire from disk once it will be duplicate on tape.

However currently I am facing issue, we have two tape drives in environment and at one time only one duplication job run at  tape drive, which means maximum two duplicate jobs run at one time and other stay in queude. Which  cause disk has been full and backup are failing with error 129, becuase until backup will not copy on tape it will not expired from disk.

Could you please suggest if we can run multiple duplication jobs at one time at one tape drive.

[Marianne]

Which NBU version (I see you have selected '7.1 and Earlier') ?

Any customization in SLP_PARAMETERS?

Have you done any SLP Parameter tuning as per the SLP Tuning Guide? (I will need to lookup the URL).

[gurminder_singh]

Hello Marianne,

Netbackup version is 7.1.0.2.

And we do not have make anychanges in the SLP Parameters it is default set

[Marianne]

Create LIFECYCLE_PARAMETERS file and add this entry:

TAPE_RESOURCE_MULTIPLIER  2

See Best practice guide for SLP and AIR.

[gurminder_singh]

Hello Marianne,

I had created file with name LIFECYCLE_PARAMETRS under \db\config folder and make entry as mentioend above by you, however it did not make any effect. still only two backup jobs are running and others are in queude.

I wanted to cross check this file would be with extention .conf ?

[gurminder_singh]

Do we also need to recycle backup services on master server after making this file or just bprdreq -rereadconf is enoug ?

I just ran bprdreq -rereadconf command on master server

[Marianne]

The filename is wrong: LIFECYCLE_PARAMETRS.

It should be LIFECYCLE_PARAMETERS with no file extention.

Please check that Notepad did not .txt to the file.

Please double-check the contents as well for typo errors.

I cannot remember if a restart is needed. 
Perform reread after checking all of the above.

[gurminder_singh]

Hello Marianne,

I created file with above mentioend name and make entried,however it did not make any effects and still two duplicate jobs are running on two tape drive.

[RiaanBadenhorst]

Duplication from disk will only run one stream at time as the image is currently not multiplexed on the disk. The behaviour is therefore to keep the image in non-multiplexed format. And that is why it can only write one stream to one tape drive.

See below the -mpx option of bpduplicate which is responsible for duplicating images.

-mpx
Specifies that when you duplicate multiplexed backups, NetBackup creates
multiplexed backups on the destination media, which reduces the time to
duplicate multiplexed backups.

Multiplexed duplication is not supported for the following operations:
■ Non-multiplexed backups
■ Backups from disk type storage units
■ Backups to disk type storage units
■ FlashBackup or NDMP backups

[gurminder_singh]

Hello Riaan,

Thanks for your useful information.

So it means we do not have way to run multiple duplicate jobs at when time  on one tape drive when backup primarly going on disk ?

Do we have any other option to get resolve from this issue , as in my environment numbers of duplicate jobs always stay in queude and jobs like NDMP which have configured to run directly on tape also stay in queude.

[RiaanBadenhorst · Accepted solution]

Hi,

The legacy reasoning behind this is that one would usually backup your slower clients to disk and then duplicate to tape at a higher speed. That was becuase you might have clients that write at 1MBps which is a bit slow for tape and can actually harm the tape drive or cause it to "pad" (write blank blocks to keep on spinning) the media which meant your media utilization was bad.

Writing to disk didn't have this problem you could write at 1MBps and its fine. Later the backup would be duplicated from the disk to the tape and you'd achieve 100MBps. So you drive didnt suffer.

So really, if you're disk read and tape write performance is good, there will be no benefit in writing multiple streams. If you're perhaps writing at 100MBPs you'd only divide that performance in 2 by writing 2 streams, i.e. 50 + 50.

Anyways, I'm getting off topic. If you're duplications are queue and there is no performance issue you need more drives or more time. If the performance is not that good you could investigate the read/write performance. But you can't run more streams.

[gurminder_singh]

Hello Riaan,

Thank you verymuch for your best advise.