usb memory sticj recovery

[James B. Byrne]

On Wed, February 28, 2018 13:54, tech-lists wrote:
> On 28/02/2018 16:19, James B. Byrne via freebsd-questions wrote:
>> I have a usb memory stick whose filesystem FreeBSD will not mount
>> because it is 'dirty'.  It is dirty because it was removed from the
>> FreeBSD host it was connected to.  I would would like to recovery
>> this
>> device if possible but my attempts to do so using fsck and fsck_ffs
>> never start because it cannot find a SUPERBLOCK.
>>
>> newfs -N gives a list of alternate sb location but fsck_ffs will not
>> acept them.
>>
>> Is there any way to manually turn ff the dirt bit and mount the
>> device?
>>
>>
>
> man 8 mount:
>
> [...]
>
> -f
>
> Forces the revocation of write access when trying to downgrade a
> file system mount status from read-write to read-only. Also
> forces the R/W mount of an unclean file system (dangerous; use with
> caution).

This did not succeed.  I do not have the exact message any more so I
cannot provide the reason stated.

>
> [...]
>
> alternatively dd the device to an image and mount the image at /mnt
> using mdconfig

Also did not work. Messages were:

mount -t msdosfs /dev/`mdconfig -f /root/usb_pki_master.img` /mnt
mount_msdosfs: /dev/md2: Invalid argument

mount -t ext3 /dev/`mdconfig -f /root/usb_pki_master.img` /mnt
mount: /dev/md3: Operation not supported by device

mount -t ufs /dev/`mdconfig -f /root/usb_pki_master.img` /mnt
mount: /dev/md4: Invalid argument

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James B. Byrne                mailto:ByrneJB at Harte-Lyne.ca
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