05-25-2021 12:50 AM
Hello,
I am using SLP for duplication to tape. There are about 50 consecutive duplication jobs every night. Each duplication job dismounts the tape after duplication. It leads to about 50 tape mounts, tape positionings before writing and tape dismounts every day.
I want to minimize the number of mounts to extend the service life of tape drives and tapes.
Is there any option to force NetBackup to keep the tape mounted between duplication jobs?
Thanks,
Lubos
Solved! Go to Solution.
06-01-2021 07:56 AM
I have checked with Veritas support. Unfortunately there is no option in NetBackup to prevent tape dismount within SLP duplication job.
05-25-2021 01:02 AM
for restores and things like database backups, NBU has the media unmount delay option.
Then in SLP world, those may not be applicable but there is RB_MPX_GROUP_UNLOAD_DELAY nbrb setting that might help
05-25-2021 01:37 AM
hi @LubosDvorak
Pls see:
https://www.veritas.com/support/en_US/doc/18716246-126559472-0/v84182756-126559472
I would recommend setting "MIN_SIZE_PER_DUPLICATION_JOB" to something like 50-100GB or even higher. Default value is 8GB and is waayyyy to low for my opinion.
Also take a look at the MAX_SIZE_PER_DUPLICATION_JOB at the same time, they go hand in hand.
Best Regards
Nicolai
05-25-2021 02:25 AM
@Mouse Thanks, I tried the RB_MPX_GROUP_UNLOAD_DELAY setting you suggested but unfortunately it had no efect in SLP :(
05-25-2021 02:28 AM
Hi @Nicolai, Thanks, I have already tuned it.
05-25-2021 02:37 AM - edited 05-25-2021 02:40 AM
hi @LubosDvorak
Consider the number of volume groups and retentions.
It's more likely a SLP job will re-use a tape already mounted if retention and volume job is the same. However if volume group and retention are different, Netbackup must unload/load a new tape in order to process the SLP's.
Just a hint :)
Update: also take a look at MAX_TIME_TIL_FORCE_SMALL_DUPLICATION_JOB
05-25-2021 03:14 AM - edited 05-25-2021 03:15 AM
hey
You can also consider to bump this parameter to a higher value:
bpgetconfig |grep -i unmount
MEDIA_UNMOUNT_DELAY = 180
like let's say 10 minutes:
echo MEDIA_UNMOUNT_DELAY=600 |bpsetconfig
bpgetconfig|grep -i unmount
MEDIA_UNMOUNT_DELAY = 600
Hope one of these provided ideas will suit you.
05-25-2021 09:25 PM
@LubosDvorakIs the SLP grouping enabled on the master server ? Worth trying to enable it. It will group SLP jobs of same priority and can help reducing in multiple SLP jobs.
Check out the SLP cheat sheet
Check for SLP Parameter "SLP.DUPLICATION_GROUP_CRITERIA"
Hope it helps.
06-01-2021 07:56 AM
I have checked with Veritas support. Unfortunately there is no option in NetBackup to prevent tape dismount within SLP duplication job.