Why

Simple, efficient way to backup zfs snapshots. Meant to work with zfs-auto-snapshot or any other tool that periodically creates snapshots. The script establishes a common base and only sends missing snapshots.

Assumptions

The local machine has ssh access to the remote machine.

Usage

The first time zfs-snapshot-sync is executed it will transfer the oldest snapshot.

<remote>@snapshot-1  ->  <local>@snapshot-1
<remote>@snapshot-2

On the next execution it will incrementally transfer the remaining snapshots including any new ones:

<remote>@snapshot-1  ->  <local>@snapshot-1
<remote>@snapshot-2  ->  <local>@snapshot-2
<remote>@snapshot-3  ->  <local>@snapshot-3

Hence all you have to do is run zfs-snapshot-sync from time to time:

ruby zfs-snapshot-sync.rb <remote-host> <remote-fs> <local-fs>

For example

ruby zfs-snapshot-sync.rb file.server.com remote-tank/stuff local-tank/same-stuff