ZFSBootMenu is a Linux bootloader that attempts to provide an experience similar to FreeBSD's bootloader. By taking advantage of ZFS features, it allows a user to have multiple "boot environments" (with different distributions, for example), manipulate snapshots before booting, and, for the adventurous user, even bootstrap a system installation via zfs recv.
In essence, ZFSBootMenu is a small, self-contained Linux system that knows how to find other Linux kernels and initramfs images within ZFS filesystems. When a suitable kernel and initramfs are identified (either through an automatic process or direct user selection), ZFSBootMenu launches that kernel using the kexec command.
For more details, see:
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