ZFS Snapshot problems

[Matthew Seaman]

Since about a week ago I've been intermittently getting a problem where
I cannot access a snapshot after creating it:

lucid-nonsense:~:# zfs snapshot zroot at test
lucid-nonsense:~:# zfs list -t snapshot
NAME         USED  AVAIL  REFER  MOUNTPOINT
zroot at test    67K      -  8.36G  -
lucid-nonsense:~:# cd /.zfs/snapshot/test
/.zfs/snapshot/test: Not a directory.

This is playing silly buggers with my backups.  Apart from that, the
system is behaving normally.  Nothing in syslog, nothing in dmesg.
The only way I've found so far to clear the problem is to reboot, but
then the problem seems to recur within a few days.

'zpool status' says everything is fine. 'zpool scrub' has no effect.

lucid-nonsense:~:# uname -a
FreeBSD lucid-nonsense.infracaninophile.co.uk 8.2-STABLE FreeBSD
8.2-STABLE #2 r231394: Fri Feb 10 20:35:13 GMT 2012
root at lucid-nonsense.infracaninophile.co.uk:/usr/obj/usr/src/sys/LUCID-NONSENSE
 amd64
lucid-nonsense:~:# zpool upgrade
This system is currently running ZFS pool version 28.

All pools are formatted using this version.
lucid-nonsense:~:# zfs upgrade
This system is currently running ZFS filesystem version 5.

All filesystems are formatted with the current version.

Any clues about how I can debug this, and hopefully prevent it happening?

	Cheers,

	Matthew

-- 
Dr Matthew J Seaman MA, D.Phil.
PGP: http://www.infracaninophile.co.uk/pgpkey


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