How to you find the parent snapshot of a zfs clone

filesystemszfs

I made a clone of zfs filesystem that has a number of snapshots. I also have several replicated copies of the filesystem.

How can I find which filesystem/snapshot a clone is attached to?

(Seems like something that should be in the docs/googlable but I haven't found anything)

Best Answer

There is a special property called origin which holds what you need. Let's assume we have a zpool tank and a filesystem tank/f1 and we create a snapshot and a clone:

 zfs snapshot tank/f1@s1
 zfs clone tank/f1@s1 tank/f2

Let's check the origin of that clone:

zfs get origin tank/f2

Output:

NAME     PROPERTY  VALUE       SOURCE
tank/f2  origin    tank/f1@s1  -

Related Solutions

Cannot destroy ZFS snapshot: dataset already exists

This issue has now been answered, courtesy of Cindy Swearingen (cindys) here: http://opensolaris.org/jive/thread.jspa?messageID=484242&tstart=0

Summary: If you do incremental receives, this might be CR 6860996:

A temporary clone is created for an incremental receive and in some cases, is not removed automatically.

1. Determine clone names:

# zdb -d <poolname> | grep %

2. Destroy identified clones:

# zfs destroy <clone-with-%-in-the-name>

It will complain that 'dataset does not exist', but you can check
again(see 1)

3. Destroy snapshot(s) that could not be destroyed previously

How to have ZFS make snapshots of a directory only when files are changed

Multiple Options:

1) cron based zfs diff (Solaris 11 Express++) and if something changed -> Snapshot() 2) dtrace zfs snapshot trigger

I have not done the latter, but read about it. 1) is probably the easiest way to do something, altought you might miss some changes, but you will not have snapshots with no changes piling up.

Regards, Robert

Best Answer

Related Solutions

Cannot destroy ZFS snapshot: dataset already exists

How to have ZFS make snapshots of a directory only when files are changed

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