Feature #10066
closedloader: Add isoboot(5) for booting BIOS systems from HDDs containing ISO images.
100%
Description
FreeBSD update: https://svnweb.freebsd.org/base?view=revision&revision=332084
A bit changed (for our needs) description:
This is part of a project for adding the ability to create hybrid CD/USB boot images. In the BIOS case when booting from something that isn't a CD we need some extra boot code to actually find our next stage (loader) within an ISO9660 filesystem. This code will reside in a MBR partition (similar to gptboot(8) from which it is derived) and looks for /boot/loader in an ISO9660 filesystem on the image.
Note the FreeBSD variant is using GPT, not MBR, this is because we do not have tools for the setup, and the use of GPT is questionable IMO (the partition start is nonstandard and there is no backup label). So the tested setup is to use MBR with isoboot stored to x86 boot partition and we can use installboot command to install the boot blocks. We will need etdump (see 9478) for the actual setup, but thats another story. The sample script is available at https://github.com/tsoome/slim_source/commit/a8cdb4a40b57fddaa152ef4a300a57a98b0f1094