specific reason OpenBSD in MBR table id 3

[ershiba]

hi bsd people,
is there any specific reason to initialize OpenBSD MBR partition to id 3?

the default installation & fdisk -i wd0 would put OpenBSD MBR partition to the last,

i am curious as of why it doesn't use the first id 0 when the whole MBR table is empty.

thank you.

[J65nko]

I really don't know.

It reminds of the Stone Age when I still was using DR-DOS. This MS-DOS compatible OS also used the last MBR partition.

You can easily change the order by using the fdisk "swap" command:

fdisk -e wd0
Enter 'help' for information
fdisk: 1> help
        help            Command help list
        manual          Show entire OpenBSD man page for fdisk
        reinit          Re-initialize loaded MBR (to defaults)
        setpid          Set the identifier of a given table entry
        disk            Edit current drive stats
        edit            Edit given table entry
        flag            Flag given table entry as bootable
        update          Update machine code in loaded MBR
        select          Select extended partition table entry MBR
        swap            Swap two partition entries
        print           Print loaded MBR partition table
        write           Write loaded MBR to disk
        exit            Exit edit of current MBR, without saving changes
        quit            Quit edit of current MBR, saving current changes
        abort           Abort program without saving current changes
fdisk: 1>

[ocicat]

Originally Posted by ershiba

is there any specific reason to initialize OpenBSD MBR partition to id 3?

No, any empty MBR partition can be used. If you want to study the code, see:

http://www.openbsd.org/cgi-bin/cvsweb/src/sbin/fdisk/