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Moving a ZFS filesystem and all of its snapshots from one zpool to another

This is how you can move all the contents of a ZFS filesystem from one zpool of block storage to another zpool of block storage. This example was done from one zpool of fiber attached LUNs to another. This can also be done from on- to off-site.

This is over in textsnippets as well.

Go into the root directory


[hostname:/] root# cd /

You can look in the filesystem and you’ll see its contents and the .zfs folder


[hostname:/] root# ls -l old-pool/filesystem
total 24
dr-xr-xr-x 3 root root 3 Mar 31 00:34 .zfs/
drwxr-xr-x 18 root root 101 Mar 11 21:45 etc/
drwx------ 4 root root 16 Feb 19 08:07 root/
drwxr-xr-x 3 root root 3 Feb 19 21:18 usr_local_etc/
drwxr-xr-x 3 root root 3 Feb 19 21:18 usr_local_var_db_mysql/

Make a final “migration” snapshot that represents the latest old-pool/filesystem


[hostname:/] root# zfs snapshot old-pool/filesystem@migration

You can see there are 3 snapshots in there


[hostname:/] root# ls -l old-pool/filesystem/.zfs/snapshot/
20060329/ 20060330/ migration/

Do a zfs backup of the oldest snapshot and pipe that into a zfs restore. This is will make the filesystem in the new-pool. You could also do this over ssh.


[hostname:/] root# zfs backup old-pool/filesystem@20060329 | zfs restore new-pool/filesystem@20060329

Now you do an incremental (-i) backup and restore using the first snapshot you used above and the one that comes after it. The key here is that incremental backups expect there to be a pre-existing new-pool/filesystem, this is how it is diffrent from the non-incremental backup above.


[hostname:/] root# zfs backup -i old-pool/filesystem@20060329 old-pool/filesystem@20060330 | zfs restore new-pool/filesystem

Do an incremental on the next pair. This happens to be with the last “migration” snapshot.


[hostname:/] root# zfs backup -i old-pool/filesystem@20060330 old-pool/filesystem@migration | zfs restore new-pool/filesystem

When you look in the new-pool/filesystem you’ll see that it has been populated from the last migration snapshot.


[hostname:/] root# ls -l new-pool/filesystem
total 24
dr-xr-xr-x 3 root root 3 Mar 31 00:34 .zfs/
drwxr-xr-x 18 root root 101 Mar 11 21:45 etc/
drwx------ 4 root root 16 Feb 19 08:07 root/
drwxr-xr-x 3 root root 3 Feb 19 21:18 usr_local_etc/
drwxr-xr-x 3 root root 3 Feb 19 21:18 usr_local_var_db_mysql/

And all three snapshots are present


[hostname:/] root# ls -l new-pool/filesystem
20060329/ 20060330/ migration/

Yes it scripts up fine as well.

·:· Posted 16 April 2006, 02:48 by Jason Hoffman to ZFS  |  Got something to say?

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