HPE Storage Users Group
https://3parug.net/

Help understanding where 11TB of snapshot data is and if it
https://3parug.net/viewtopic.php?f=18&t=3399
Page 1 of 1

Author:  mokins [ Fri May 15, 2020 9:22 am ]
Post subject:  Help understanding where 11TB of snapshot data is and if it

Hi.

Can anyone please help me. I have been asked to explain where 11TB of data is and if it is still needed.

When I expand the capacity tree for one of my 3PARs, under Allocated > Volumes > CPGs > Snapshot, I can see that it is reporting 11,310.667 GiB (20.24%) but I have no idea what this is for and if it is still needed or not. (attached a picture at that always help!)
Attachment:
SY36-3PAR-2 Snapshot Space.JPG
SY36-3PAR-2 Snapshot Space.JPG [ 30.56 KiB | Viewed 14347 times ]


Is anyone please able to assist me in finding what this space is being used for and if it is still valid and not something old.

3PAR: 8450 running 3.2.2 (MU6) with P96, P99 installed
Disks: 16 x 371 GiB SSD + 112 x 446 GiB SSD
This is the DR site of a pair with Remote Copy configured and working but as far as I can see, we are only replicating about 8TB via RC.


Many Thanks

Author:  MammaGutt [ Fri May 15, 2020 10:49 am ]
Post subject:  Re: Help understanding where 11TB of snapshot data is and if

CLI -> showvv -s

And/or showvvcpg

And FWIW, there has been a lot of patches to 3.2.2 MU6, I think P144 was the last to contain reclaim enhancements.

Author:  mokins [ Fri May 15, 2020 10:55 am ]
Post subject:  Re: Help understanding where 11TB of snapshot data is and if

Hi.
Thanks, tried them previously and if I am reading them correctly, they are only adding upto 8TB... not the 11TB.

I have grabbed screen output for both commands in a text file and attached it.

Many Thanks

Attachments:
SY36-3PAR-2 CLI Output.txt [22.36 KiB]
Downloaded 1224 times

Author:  MammaGutt [ Fri May 15, 2020 10:57 am ]
Post subject:  Re: Help understanding where 11TB of snapshot data is and if

The first picture shows RAW disk usage. Showvv shows net usage (after RAID).

Will look at attachment later.

Author:  MammaGutt [ Fri May 15, 2020 11:59 am ]
Post subject:  Re: Help understanding where 11TB of snapshot data is and if

You have 8 299 520 MiB allocated to snap space, of which 6168375 MiB is used. You have some (100-200 000 MiB) you can release by doing "freespace -f <vvname>" on the VVs that have Snp Rsvd space and 0 MiB in Snp Used.

Most of the snap space is locked up in snapshots, some is used for periodic/async remote copy.

Assuming R5 3+1 you will have 33% RAID overhead 8 299 520 * 1.33 = ~11 040 000 MiB, so I'm guessing you have a few MiBs that could be released by doing compact cpg on CPG-COPY-SSD-480GB-R5-1.

As mentioned I would really suggest to schedule at least a patch upgrade if not a full OS upgrade on these systems. You are really far behind on patches (I think about 3 1/2 years) and 3.3.1 offers some nice features for a new dedupe version since you got a few dedupe volumes.

Author:  mokins [ Fri May 15, 2020 12:08 pm ]
Post subject:  Re: Help understanding where 11TB of snapshot data is and if

Thank you ever so much for this, I can follow and understand tour reply and it is a great help.
As for upgrading the OS, it is on the to do list... I will just move it up the list a bit to get it done sooner.

Many Thanks

Page 1 of 1 All times are UTC - 5 hours
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
http://www.phpbb.com/