If you updated your zpool to v28, then you might get hit with zfs destroy -r bug (regression?). This bug prevents deleting snapshots recursively if you don't have snapshot on filesystem from which you recursively try to delete snapshots.
For example, you have tank/b@snapshot, but don't have tank@snapshot, then
zfs destroy -r tank@snapshotwon't work as it used to be (won't delete any snapshots). Using -zpool28fix workaround zfSnap will delete every snapshot (that zfSnap would normally delete) one by one. Deleting snapshots will be slower, but at least it will work.
This problem also persists on OpenIndiana dev-148 with zpool v28, however on Oracle Solaris 11 Express 2010.11 with zpool v31 the problem is gone.
You can check version of zpool by running
zpool get version tankIf your zpool is at v15 or v14, then you don't need to use -zpool28fix
Some related mails on mailinglist:
zfSnap is licensed with BEER-WARE license
# "THE BEER-WARE LICENSE":
# <graudeejs@yandex.com> wrote this file. As long as you retain this notice you
# can do whatever you want with this stuff. If we meet some day, and you think
# this stuff is worth it, you can buy me a beer in return Aldis Berjozazfs + snap => zfssnap => zfSnap
Major.Minor.Fix
zfSnap git repository https://github.com/graudeejs/zfSnap
https://github.com/graudeejs/zfSnap/issues
If you like zfSnap send me a feedback (In English, Latvian or Russian languages)