I hate to bitch but bitch I must

Polytropon freebsd at edvax.de
Sat Oct 17 23:03:08 UTC 2009

On Sat, 17 Oct 2009 23:47:56 +0100, krad <kraduk at googlemail.com> wrote:
> he has a raw file system on that device, ie dangerously dedicated, no
> partitions etc

That's the standard mode for data disks that are not intended
to be booted from. It's usable for USB sticks as well. There's
no need for a slice.

The comment "no partitions" is partially incorrect, because 
there is "kind of" a partition on the device. Note that this
partition spans the whole device, which is indicated by the
letter "c". In this case, /dev/da0 is /dev/da0c. I think it
was in FreeBSD 5 when the "c" for "the whole" disk / partition
has been "removed" (well, it's still there, it's the reason
that you usually can't create da0s1a, da0s1b AND da0s1c,
because da0s1c is da0s1), from the disk devices as well as
from the acd devices (acd0c is acd0 today).

At least, it's correct to say that there's one file system
on the disk. Tools like fdisk and bsdlabel haven't been
involved in creating it, just

	# newfs /dev/da0

was the tool of choice.

I'd like to add that I've used this method on PDs (phase
change discs) as well; they were introduced as da0 to the
device directory. No need for slices because the whole disc
should be used as one volume.

A final note: You can, however, create multiple partitions
on a device with no underlying slice, such as da0a, da0b,
da0d, da0e etc. And FreeBSD can boot from it without problems.
It's always the MICROS~1 stuff that has problems with it. :-)

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

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