GEOm label inconsistency.

I have two USB drives... so I decided that using geom_label.ko would
be handy to make scripts work for mounting and unmounting the drives
(as I could never ensure that they came up in the same order).

I was pleased to find that my various pieces of MSDOS flash seemed to
work just fine.  /dev/msdosfs/<blah>

However, of my two USB drives (actual hard disks) ... both formatted
with a UFS filesystem covering the whole drive, one puts a label in
/dev/ufs and the other does not.

The one that works is a 30 gig laptop drive in a USB2 bus powered (two
plugs) carrier.  It has an "fdisk -I" MBR and I formatted the da0s1c
partition.  Now... geom_label recognises da0s1 as the labelled
partition ... but that really doesn't matter to me ... it works.

The one that doesn't work is a 120G drive in a USB2 enclosure from
iomega.  Again, it has an "fdisk -I" MBR and a whole disk ufs
filesystem.  geom_label does not recognise it for some reason.

Turning on the debug for geom_label, I find:

da1 at umass-sim1 bus 1 target 0 lun 0
da1: <IC35L120 AVV207-0 V24O> Fixed Direct Access SCSI-0 device 
da1: 40.000MB/s transfers
da1: 117800MB (241254720 512 byte sectors: 255H 63S/T 15017C)
GEOM_LABEL[1]: UFS1 file system detected on da1s1.
GEOM_LABEL[1]: MSDOS (FAT32) file system detected on da1s1.
GEOM_LABEL[1]: UFS1 file system detected on da1s1c.
GEOM_LABEL[1]: MSDOS (FAT32) file system detected on da1s1c.
GEOM_LABEL[1]: UFS1 file system detected on da1s1g.
GEOM_LABEL[1]: MSDOS (FAT32) file system detected on da1s1g.

Now... the drive _used_ to have a MSDOS filesytem on it... but it has
since been:

a) fdisk'd to type 165
b) bsdlabeled
c) formatted and used for most of 2 years as a UFS filesystem

Does this mean that geom_label's testing of filesysem type is weak?
Is there a workaround whereby I blank a sector not used by UFS?
Should geom_label take hints from the mbr type?

Dave.

-- 
============================================================================
|David Gilbert, Independent Contractor.       | Two things can only be     |
|Mail:       dave_at_daveg.ca                    |  equal if and only if they |
|http://daveg.ca                              |   are precisely opposite.  |
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