Musings on ZFS Backup strategies

[Ben Morrow]

Quoth Phil Regnauld <regnauld at x0.dk>:
> 
> > The only risk that makes me uncomfortable doing this is that the pool is
> > always active when the system is running.  With UFS backup disks it's
> > not -- except when being actually written to they're unmounted, and this
> > materially decreases the risk of an insane adapter scribbling the
> > drives, since there is no I/O at all going to them unless mounted. 
> > While the backup pool would be nominally idle it is probably
> > more-exposed to a potential scribble than the UFS-mounted packs would be.
> 
> 	Could "zpool export" in between syncs on the target, assuming that's not
> 	your root pool :)

If I were feeling paranoid I might be tempted to not only keep the pool
exported when not in use, but to 'zpool offline' one half of the mirror
while performing the receive, then put it back online and allow it to
resilver before exporting the whole pool again. I'm not sure if there's
any way to wait for the resilver to finish except to poll 'zpool
status', though.

Ben