Can't create PSM files - volume is too fragmented

[William Robertson_3]

Hi there

I am receiving the following error:
"Cannot create PSM files because the volume is too fragmented."

when I try to create snapshots on my NAS b2000v2 device. Everything was working fine until I extended my storage from 1TB to 1.6TB

Any/all ideas welcome,
Thanks
William R.

[CA1118839]

William,

I am no PSM expert, but I have looked at the FAQ PSM/SAK document a few times
http://www.cdp.com/library/PSMFAQ.pdf

If it were me, I would go ahead and defragment the volume and see if you can create a snapshot and the error goes away.

[William Robertson_3]

Hi Keith

Thanks for the reply. Regarding the DEFRAG of the volume, I have run Microsoft's Defrag and it failed dismally (The Defrag utility would startup and analyse, but as soon as I say Defrag it would run for a few minutes and then just complete without providing any stats...)

So I then downloaded a trial version of Diskeeper Enterprise Edition 9.0, and managed to complete 3 successful Defrags. But each time I still get the error about not being able to create a Persistent Image because the volume is too fragmented.

I have run the CLEANVOL utility to remove all PSM files etc, and then run a defrag again - still no luck. I have even tried aking my PSM Cache file very small (5% of 1.6TB) - This also didn;t work.

I also tried increasing the Granular Size (GRANSIZE.EXE) to 128, but this also didn't help...

I am really running out of ideas here. Does anyone have any more suggestions PLEEEEZZZZZZZZ.

Thanks
William R.

[CA1118839]

Okay .. here is another link to help troubleshoot.
http://www.cdp.com/library/ErrorCodes.pdf

Version 2/W2K based HP NAS products used CDPs PSM for snapshots.

Look at the error code associated with PSM-VOLUME_TOO_FRAGMENTED. The error code offers a few basic steps to fix the error, although you may have done this already.

Top of the PSM/SAK Event Log Error Codes page has the information you will need if you choose to contact HP Support. Wait a little bit because I will ask one of the NAS support engineers to look at this issue.

Also, the W2K3 HP NAS products use Microsofts snapshot, not CDPs. There is an OS (W2K=>W2K3) upgrade kit for the b2000v2, see:
http://h18006.www1.hp.com/products/storageworks/nas/upgradekits.html

[CA1083075]

Hi William,

In addition to what Keith said, this error typically means that the free space is too fragmented and not necessarily the actual data that is fragmented. When you run the defrag with Diskeeper, are you also telling it to defrag free space? If you are not, try running the Diskeeper defrag again specifying to defrag the free space.

The Microsoft defrag app defragments files, but it does NOT defragment free space. Therefore, since the free space is still fragmented, the PSM cache file gets created with all those fragments. And, as a result, you still get the volume is too fragmented error. This also would explain why the MSFT defrag app only runs for a minute and completes without any errors (running cleanvol and gransize would mean that you deleted all the current snapshots so no data would be in the snapshot volume area).

Try that and let us know.

- Monty

[William Robertson_3]

Thanks Keith & Monty for your replies.

When I checked again this mornign I was amazed to see that last night a snapshot was in fact created successfully (I have a schedule that runs every night) - and my only conclusion as to why this started working suddenly after 2 weeks of nothing, is that I have had Diskeeper running on a daily schedule as well. All I can presume that that Diskeeper eventuallt managed to defrag the volume to an extent that the PSM was happy once again.

Unfortunately, the last time that I configured the PSM Settings, I set my Cache Size too small (this was one of my tests), so I now had to run CLEANVOL again so that I could set the Cache Size to 20%, but when I tried to take another snapshot on the new Cache file I got the same Fragementation errors again... Hmmm...

Anyway, so now I have created my PSM Cache file at the correct size, and scheduled Diskeeper to run 2x per day, and to include the Free Space Consolidation as you suggested.

Hopefully after all of this my problem will be resolved, I will keep you guys posted.

Thanks again for your assistance so far.