ZFS ZFS backup to a tape

[Oko]

I am having a hard time finding any reference how to back up ZFS data sets to a tape drive. I recently learned that FreeNAS doesn't have even tape drive drivers included but the reason might be that they don't have GUI for it. Could anybody kindly share any peace of documentation which is ZFS specific with respect to backup to a tape drive. I would also appreciate any recommendations with respect to tape drive recorders which can be purchased in U.S.

 

[SirDice]

I doubt you will find a complete example. The principle however is the same as for any other tape backup. Use zfs send to create the backup, send the resulting file to the tape using tar(1) (you can pipe one to the other).

 

[kpa]

There's a problem though with that approach. The data streams produced by zfs send are not designed to be stored, only to be received with zfs receive and replicated on another ZFS pool. There is zero redundancy or error checking in the data stream and if there's even one bit flipped at the wrong place the whole stream could be unusable. I would at least compress the data with gzip(1) before writing it onto a tape.

http://www.solarisinternals.com/wik...ces_Guide#Recommendations_for_Saving_ZFS_Data

 

[Terry_Kennedy]

I doubt you will find a complete example. The principle however is the same as for any other tape backup. Use zfs send to create the backup, send the resulting file to the tape using tar(1) (you can pipe one to the other).

Depending on how big your backups are, they may not fit on one tape. At least on FreeBSD 8.x, the system tar(1) command is bsdtar, which does not support multi-tape archives. The archivers/gtar port does support this functionality and you may want to investigate it.

You might also find the "Backups" section of my RAIDzilla II article useful, as it deals with ZFS backups.