> I have an OpenBSD 3.7 i386 installation on an external usb-enclosure.
> I have some space left, and I would like to create an msdos partition
> (to transfer files between windows and OpenBSD).
>
> I have tried to create one using OpenBSD's fdisk; then I have
> formatted the new partition in windows xp.
>
> But now I don't see how to access the new partition from OpenBSD -- it
> does not appear in disklabel, so I don't know how to mount it.
>
> Here is some relevant data:
>
> mhv2040at# dmesg | grep sd0
> sd0 at scsibus1 targ 1 lun 0: <FUJITSU, MHV2040AT, 0000> SCSI0 0/direct fixed
> sd0: 38154MB, 38154 cyl, 64 head, 32 sec, 512 bytes/sec, 78140161 sec total
> dkcsum: sd0 matched BIOS disk 80
> root on sd0a
>
> mhv2040at# fdisk sd0
> Disk: sd0 geometry: 4864/255/63 [78140160 Sectors]
> Offset: 0 Signature: 0xAA55
> Starting Ending LBA Info:
> #: id C H S - C H S [ start: size ]
> ------------------------------------------------------------------------
> *0: A6 0 1 1 - 4177 254 63 [ 63: 67119507 ] OpenBSD
> 1: 0C 4178 0 1 - 4308 254 63 [ 67119570: 2104515 ] Win95 FAT32L
> 2: 00 0 0 0 - 0 0 0 [ 0: 0 ] unused
> 3: 00 0 0 0 - 0 0 0 [ 0: 0 ] unused
Note 67119570 and 2104515 above
That is the piece of disk you want to use.
> 16 partitions:
> # size offset fstype [fsize bsize cpg]
> a: 524225 63 4.2BSD 2048 16384 255 # Cyl 0*- 255
> b: 2097152 524288 swap # Cyl 256 - 1279
> c: 78140161 0 unused 0 0 # Cyl 0 -
> 38154*
> d: 524288 2621440 4.2BSD 2048 16384 256 # Cyl 1280 - 1535
> e: 2097152 3145728 4.2BSD 2048 16384 323 # Cyl 1536 - 2559
> f: 4194304 5242880 4.2BSD 2048 16384 323 # Cyl 2560 - 4607
> g: 524288 9437184 4.2BSD 2048 16384 256 # Cyl 4608 - 4863
> h: 4194304 9961472 4.2BSD 2048 16384 323 # Cyl 4864 - 6911
> i: 2097152 14155776 4.2BSD 2048 16384 323 # Cyl 6912 - 7935
> j: 2097152 16252928 4.2BSD 2048 16384 323 # Cyl 7936 - 8959
> k: 2097152 18350080 4.2BSD 2048 16384 323 # Cyl 8960 - 9983
> l: 4194304 20447232 4.2BSD 2048 16384 323 # Cyl 9984 - 12031
> m: 8388608 24641536 4.2BSD 2048 16384 323 # Cyl 12032 - 16127
> n: 34089426 33030144 4.2BSD 2048 16384 323 # Cyl 16128 -
> 32773*
# disklabel -E sd0
> a p
offset: [67119570] 67119570
size: [2104515] 2104515
FS type: [4.2BSD] MSDOS
If the above does not work, try typing the 'b' command and using '*'
to use the whole disk, then repeat.
It will most likeley guess the size of that partition you want.
OpenBSD only uses the MBR/PBR crud to find the disklabel, then
it gives you a max of 15 (16) partitions located using absolute
addressing.
This is well documented in the FAQ. And it works almost the
same on all our architectures, unlike other operating systems
that do something different for every architecture.
> mhv2040at# ll /dev/sd0*
> brw-r----- 1 root operator 4, 0 Sep 4 22:33 /dev/sd0a
> brw-r----- 1 root operator 4, 1 Sep 4 22:33 /dev/sd0b
> brw-r----- 1 root operator 4, 2 Sep 4 22:33 /dev/sd0c
> brw-r----- 1 root operator 4, 3 Sep 4 22:33 /dev/sd0d
> brw-r----- 1 root operator 4, 4 Sep 4 22:33 /dev/sd0e
> brw-r----- 1 root operator 4, 5 Sep 4 22:33 /dev/sd0f
> brw-r----- 1 root operator 4, 6 Sep 4 22:33 /dev/sd0g
> brw-r----- 1 root operator 4, 7 Sep 4 22:33 /dev/sd0h
> brw-r----- 1 root operator 4, 8 Sep 4 22:33 /dev/sd0i
> brw-r----- 1 root operator 4, 9 Sep 4 22:33 /dev/sd0j
> brw-r----- 1 root operator 4, 10 Sep 4 22:33 /dev/sd0k
> brw-r----- 1 root operator 4, 11 Sep 4 22:33 /dev/sd0l
> brw-r----- 1 root operator 4, 12 Sep 4 22:33 /dev/sd0m
> brw-r----- 1 root operator 4, 13 Sep 4 22:33 /dev/sd0n
> brw-r----- 1 root operator 4, 14 Sep 4 22:33 /dev/sd0o
> brw-r----- 1 root operator 4, 15 Sep 4 22:33 /dev/sd0p
>
> mhv2040at#
>
> I think sd0o and sd0p are the leftovers from the installation
> procedure (I might have created sd0o and sd0p, but deleted it during
> the installation).
Don't do that. Leave them alone. There is never any
need to delete such things.
