Reformatting external harddrive

Polytropon freebsd at
Tue May 12 18:02:03 UTC 2009

On Tue, 12 May 2009 13:41:37 -0400, Daniel Underwood <djuatdelta at> wrote:
> I have no idea why there is more than 1 partition on this disk.

I think I just saw one partition (slice in FreeBSD) in your output.

> The data for partition 1 is:
> [blah]
> The data for partition 2 is:
> The data for partition 3 is:
> The data for partition 4 is:

> Every time I tried to fdisk (or
> perhaps it was mkfs.ext3) on in linux, I got errors about a "bad
> superblock" (which I understand somehow relates to the journaling
> mechanism of ext3).

UFS has superblocks, too.

> Therefore it is my hope that by reverting to the lowest level tools in
> FreeBSD to reformat the drive (if that's even the appropriate step to
> take) I can reclaim the ~300GB drive for external storage/backups.

These tools are basic tools, not lowest level. In fact, they operate
on a very high level of functionality. :-)

If you want to use the disk as an external backup storage, the simplest
thing is to

	# newfs /dev/da0

and then just mount it. If you're not going to slice and partition it,
there's no need for fdisk or bsdlabel. The device /dev/da0, formerly
/dev/da0c, refers to "the one whole partition on DA device 0", as
/dev/da0s1c would refer to "the one whole partition covering the
1st slice of DA device 0"; you can, however, have more than one
slice on that disk, and different partitions within each slice,
such as /dev/da0s2g. But according to your requirement for a backup
storage, using the whole disk altogether would surely be the best

You can then enter a line like

	/dev/da0	/backup		ufs	rw,noauto	2	2

in your /etc/fstab, and then use

	# mount /backup

do your backups or recoveries, e. g. with cpdup or tar, then use

	# umount /backup

It's quite simple to do so. :-)

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

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