Two points
1. space reclamation on NetApp happens in background. For a large file it can take quite a long time.
2. deleting snapshot does not mean you will free anything :) Remember that snapshot shares blocks with other snapshots and active file system. So deleting snapshot simply decrements reference counts. You can estimate how much space will be actually freed *before* deleting using "snap reclaimable".
--- With best regards
Andrey Borzenkov Senior system engineer Service operations
-----Original Message----- From: toasters-bounces@teaparty.net [mailto:toasters-bounces@teaparty.net] On Behalf Of Jeff Cleverley Sent: Saturday, December 17, 2011 4:05 AM To: toasters@teaparty.net Subject: Disk space increasing after snapshots are deleted.
Greetings,
We have a 8.0.1 filer that runs as a NearStore for SV backups. The group using this normally kept 120 nightly backups. The aggregates were getting full so they decided to delete all snapshots older than 90 days. This was done with a script using snap delete <vol> <snapshot> with a list of snapshots fed into the command.
Some of the lists were not in reverse order so it deleted nightly.91 before nightly.119. I know deleting them in this type of order will work anyway, but it causes the system to do more processing.
The problem is the disk space is continuing to grow on all volumes in the aggregates. An aggr show_space of the aggregates shows everything increasing in used space. The volumes have no space reservation.
I'm trying to figure out how this mass deletion of snapshots (several hundred) is causing an increase in space usage. Any ideas?
Thanks,
Jeff