ZFS Send / Receive Recursively Without Properties

[Eric A. Borisch]

On Monday, January 5, 2015, Tim Gustafson <tjg at ucsc.edu> wrote:
>
> If I drop the -R parameter to ZFS send, then it does not overwrite the
> mountpoints, but it also does not destroy the non-existent snapshots
> on the server "B".  Snapshots on server "A" are automatically
> destroyed by a script after 7 days, and we don't want to accumulate
> snapshots on server "B" that have been destroyed from server "A".  We
> also would prefer to not run a snapshot purging script on server "B"
> because ultimately this solution will be used for multiple source
> servers, and each of them have different snapshot retention policies
> that I'd like to not have to maintain in two separate places.
>

I was doing this too, until I realized that an accidental (fat fingered)
removal of file systems/snapshots on the source side then flows through to
remove it on the backup side as well. Granted, you may want the removal to
happen on both sides, but for my tastes, removals of whole file systems on
the backup shouldn't happen without user interaction.

This concern led me to avoid -R for automated transfers, and necessitated a
snapshot expiry script on the backup side. I like my backup to protect me
from at least one level of fat-fingers. :)

This has the added benefit that you can have a smaller retain count on the
active source, but keep files longer on the backup side. I've also started
using holds on the backup side as a belts-and-suspenders approach.

Just my 2c.

 - Eric