backup msdos slice

Polytropon freebsd at
Mon Mar 2 18:20:31 PST 2009

On Mon, 2 Mar 2009 14:10:42 -0500, Jerry <jerrymc at> wrote:
> So, what I would like is something that would dump the MS slice
> to a FreeBSD file or media written in the FreeBSD world and that
> I could then pick out files and directories somewhat like I do
> using restore on a dump file. 

There should be a simple way: Just dd the FAT partition into a file.
You can then backup this file in FreeBSD (by any way you want).
In order to access files inside the dd image you can simply mount
it using the md (memory disk) facility.

An example (not verified, I don't have any MICROS~1 around); I'll
assume that /dev/ads2c is the FAT file system in question (again,
I do admit that I don't know how FAT partitions occur as device
files in FreeBSD).

	% dd if=/dev/ads2c of=fat.dd bs=1m
	12345678+1 records in
	12345678+1 records out

Now you've got fat.dd. You can backup this file or just backup
content parts of it.

	% sudo mdconfig -a -t vnode -u 10 -f fat.dd
	% mount -t msdosfs -o ro /dev/md10 /mnt

You now can access the files in fat.dd from the /mnt subtree. Be
sure to check

	% man mount_msdosfs

for additional options you might need (character conversion, large,
longnames, mask, ... - I don't exactly know what to use).

Now you can partwise plusgood backup files from within /mnt, using
your favourite backup method (tar to tape, rsync to remote machine
or what you prefer).

> Basically, I want to back up the MSDOS slice (I know MS calls it
> a primary partition) from the FreeBSD side of things.   I can read
> and write the slice nicely from FreeBSD, but not dump/restore.

Now you can. :-)

>From Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...

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