CDBOOT(8)

NAME
cdboot - i386-specific second-stage CD-specific bootstrap

DESCRIPTION
cdboot is a modified version of the i386 second-stage bootstrap program, boot(8), configured to be run by the OpenBSD El Torito CD-ROM boot sector cdbr. cdboot will look for an /etc/boot.conf configuration file on the CD-ROM. If it finds one, it processes the commands within it. boot.conf processing can be skipped by holding down either Control key as cdboot starts.

cdboot then sits in a loop, processing commands given by the user. It accepts all the commands accepted by boot(8).

If no commands are given for a short time, cdboot will then attempt to load an OpenBSD kernel from the CD. It first looks for the install kernel bsd.rd in the standard i386 release directory (e.g. /3.6/i386/bsd.rd), then for /bsd. It may be told to boot an alternative kernel, either by commands in the boot.conf file, or by commands typed by the user at the boot> prompt.

FILES
/usr/mdec/cdboot
    CD-specific second-stage bootstrap
/etc/boot.conf
    cdboot configuration file (read from CD)

EXAMPLES
Boot the install kernel:

    boot> bsd.rd

SEE ALSO
boot(8), boot_i386(8), mkhybrid(8) El Torito Bootable CD-ROM Format Specification, Version 1.0, January 25, 1995, Curtis E. Stevens, Phoenix Technologies, Stan Merkin, IBM.

HISTORY
The cdboot program first appeared in OpenBSD 3.6.

CAVEATS
By default, many CD creation programs restrict filenames to the MS-DOS 8.3 format. Unless this is changed, cdboot will not be able to read its boot.conf(5) file. For example, with mkhybrid(8) the -l option should be specified.

BUGS
The ls command does not work on ISO 9660 (cd9660) filesystems, which are used on most CDs.