Python script for automatically creating ZFS snapshots when installing/removing/upgrading packages through APT. The snapshots are only created on the filesystems that are going to be affected by the changes, minimizing the number of snapshots (and possible wasted space).

Install

There's no install script (or package) yet, so it's all manual for now. There's two hard external dependencies, Python 3 and the Python APT bindings. If available, the Python ZFS bindings are also used. The ZFS bindings are only available (or at least packaged) for ZFS on Linux >=0.8.0, so if you're using your distro's packages, the bindings are only available for Debian >=buster and *buntu >=eoan. To install (skip the ZFS bindings if they're not available):

sudo apt install python-apt python3-pyzfs

After that, copy the script to /usr/local/bin and add the APT config file:

sudo mkdir -p /usr/local/bin
sudo cp ./zfs_apt_snapshot.py /usr/local/bin/zfs-apt-snapshot
sudo chmod +x /usr/local/bin/zfs-apt-snapshot
sudo cp ./90apt-zfs-snapshot /etc/apt/apt.conf.d/

You can check out the available options with zfs-apt-snapshot --help. I'd recommend editing /etc/apt/apt.conf.d/90apt-zfs-snapshot to purge old snapshots as well (not on by default for safety).