FreeBSD and beadm

One of Solaris’ ZFS features is boot environments, where you can install multiple versions of the core operating systems and choose which one to boot into. Boot environments take a lot of the risk out of upgrades; if an upgrade goes bad, you can easily roll back to the previous version.

Boot environments are built on top of ZFS. Recent FreeBSD installers create fine-grained datasets rather than a single large dataset, which means you can leverage boot environments on FreeBSD.

Boot environment...