This installs Daisuke Aoyama's isboot kernel module, which allows
booting FreeBSD directly from an iSCSI root disk. If your BIOS
supports iSCSI you may configure your target settings in the BIOS
and boot directly. If not, you may PXE boot using software that
contains iSCSI support such as iPXE. The module reads the iSCSI
Boot Firmware Table (IBFT) to configure the network and re-attach
the volume once the kernel begins execution.

WWW: https://github.com/jnielsendotnet/isboot