beadm is a tool for managing ZFS boot environments on Linux. These boot environments provide a way to swap between multiple Linux installations (or versions of the same installation) on a single system. It is also commonly used to facilitate safe system updates and easy rollback if problems occur.

beadm traces its history back to the original beadm on Solaris (and later illumos), as well as bectl on FreeBSD. It is not the first attempt to bring these tools to Linux, but it does have some notable differences in approach:

• It is designed for Linux desktop users, and so makes use of D-Bus, Polkit, and other Linux-specific platform features (e.g. systemd) by default.

• It benefits from the speed and correctness guarantees of Rust. Anecdotally, it feels much more responsive than other Linux implementations (which are largely written in Shell). It is also much easier to modify safely than the illumos or FreeBSD implementations, which are written in C.

• It completely sidesteps the complexity of interacting with the bootloader. Instead, beadm assumes you are using a bootloader that can natively understand boot environments (e.g. ZFSBootMenu).

• The traditional beadm commands to list, create, activate, destroy, rename, and mount boot environments are all available.

• First-class support for attaching a description to boot environments and snapshots.

• A D-Bus service exposes boot environments to graphical interfaces without the need to parse CLI output or use pkexec. This also enables writing applications that can be distributed via Flakpak.

• Polkit integration for fine-grained permissions and an authorization UI, rather than requiring sudo for every operation.

• APT and APK package manager integration.

The beadm binary can be built with Cargo, but the project requires Meson and scdoc for a real installation. The usual Meson workflow applies:

meson setup build
meson compile -C build
meson install -C build

Where meson install usually requires escalated privileges.

Several features (including D-Bus and systemd integration) are enabled by default if the host system supports these tools. See meson_options.txt for all possible options.

Note: for distros with an older version of Polkit, policy files installed to /usr/local/share may not be picked up correctly. Creating a symlink can alleviate this:

$ ln -s /usr/local/share/polkit-1/actions/ca.kamacite.BootEnvironments1.policy \
  /usr/share/polkit-1/actions/ca.kamacite.BootEnvironments1.policy