zfs-auto-snapshot

An alternative implementation of the zfs-auto-snapshot service for Linux that is compatible with ZFS on Linux.

Automatically create, rotate, and destroy periodic ZFS snapshots. This is the utility that creates the:

• @zfs-auto-snap_frequent,
• @zfs-auto-snap_hourly,
• @zfs-auto-snap_daily,
• @zfs-auto-snap_weekly, and
• @zfs-auto-snap_monthly

snapshots if it is installed.

This program is a posixly correct bourne shell script. It depends only on the zfs utilities and cron, and can run in the dash shell (using the scripts in etc).

Installation using cron

wget https://github.com/zfsonlinux/zfs-auto-snapshot/archive/master.zip
unzip master.zip
cd zfs-auto-snapshot-master
make install

Installation using systemd

wget https://github.com/zfsonlinux/zfs-auto-snapshot/archive/systemd.zip
unzip systemd.zip
cd zfs-auto-snapshot-systemd
make install enable

Scheduling

See systemd timers.

You can find some example .timer files in the timers/ directory of this repo. They will be installed when you run make install from the systemd git branch.

If you wish to edit the timers, you will find them in the /usr/local/lib/systemd/system/ directory. Save the edited timers to /etc/systemd/system/ directory to override the default timers.

Managing Which Pools to Snapshot

By default, the script will snapshot all pools automatically, unless they have the com.sun:auto-snapshot property set to false.

To check the status of this property for all of your pools and datasets, run the following command:

sudo zfs get com.sun:auto-snapshot

If you see an output like the following, then snapshots are enabled on this pool:

NAME     PROPERTY               VALUE                  SOURCE
archive  com.sun:auto-snapshot  -                      -

To disable snapshots on this pool, issue the following command:

sudo zfs set com.sun:auto-snapshot=false archive

We can check with zfs get again, and this time our output should look like the following. If we see this, we know that snapshots have been disabled on this pool:

NAME     PROPERTY               VALUE                  SOURCE
archive  com.sun:auto-snapshot  false                  local

To disable snapshots on a single dataset, the command is very similar:

sudo zfs set com.sun:auto-snapshot=false archive/dataset