1BFS FILESYSTEM FOR LINUX
2========================
3
4The BFS filesystem is used by SCO UnixWare OS for the /stand slice, which
5usually contains the kernel image and a few other files required for the
6boot process.
7
8In order to access /stand partition under Linux you obviously need to
9know the partition number and the kernel must support UnixWare disk slices
10(CONFIG_UNIXWARE_DISKLABEL config option). However BFS support does not
11depend on having UnixWare disklabel support because one can also mount
12BFS filesystem via loopback:
13
14# losetup /dev/loop0 stand.img
15# mount -t bfs /dev/loop0 /mnt/stand
16
17where stand.img is a file containing the image of BFS filesystem.
18When you have finished using it and umounted you need to also deallocate
19/dev/loop0 device by:
20
21# losetup -d /dev/loop0
22
23You can simplify mounting by just typing:
24
25# mount -t bfs -o loop stand.img /mnt/stand
26
27this will allocate the first available loopback device (and load loop.o
28kernel module if necessary) automatically. If the loopback driver is not
29loaded automatically, make sure that your kernel is compiled with kmod
30support (CONFIG_KMOD) enabled. Beware that umount will not
31deallocate /dev/loopN device if /etc/mtab file on your system is a
32symbolic link to /proc/mounts. You will need to do it manually using
33"-d" switch of losetup(8). Read losetup(8) manpage for more info.
34
35To create the BFS image under UnixWare you need to find out first which
36slice contains it. The command prtvtoc(1M) is your friend:
37
38# prtvtoc /dev/rdsk/c0b0t0d0s0
39
40(assuming your root disk is on target=0, lun=0, bus=0, controller=0). Then you
41look for the slice with tag "STAND", which is usually slice 10. With this
42information you can use dd(1) to create the BFS image:
43
44# umount /stand
45# dd if=/dev/rdsk/c0b0t0d0sa of=stand.img bs=512
46
47Just in case, you can verify that you have done the right thing by checking
48the magic number:
49
50# od -Ad -tx4 stand.img | more
51
52The first 4 bytes should be 0x1badface.
53
54If you have any patches, questions or suggestions regarding this BFS
55implementation please contact the author:
56
57Tigran A. Aivazian <tigran@veritas.com>
58