Unable to mount USB Flash memory created on CentOS
freebsd at edvax.de
Fri Jul 28 19:24:42 UTC 2017
On Fri, 28 Jul 2017 15:14:21 -0400, James B. Byrne wrote:
> On Fri, July 28, 2017 14:51, Polytropon wrote:
> > On Fri, 28 Jul 2017 13:22:06 -0400, James B. Byrne via
> > freebsd-questions wrote:
> >> On my new FreeBSD workstation I am trying to read data off of a USB
> >> 'key' flash memory stick recorded using rsync on a CentOS-6 system.
> >> I was able to do this successfully up until the point that I inserted
> >> another usb stick. Now I cannot mount or read either.
> > Did you unmount the previous stick correctly?
Okay, so no general problem with file systems; I assume you
are using FUSE here.
> > When you say it was "recorded" with CentOS, which file system
> > has been used? Or is it a "raw" file (no file system at all,
> > output written directly to the device)?
> ext2fs. I was formerly able to read these usb sticks on the new
> FreeBSD based workstation. The problem only surfaced when I inserted
> a second usb flash drive.
That shouldn't interfere with already mounted extfs volumes,
except the DE's automounter going crazy...
> >> I probably made things worse by first removing both keys from the
> >> host and then deleting the contents of /media. However, that is
> >> done.
> > That should not be a big problem, as /media is usually populated
> > automatically by a desktop environment's automounter, or manually
> > by the system administrator (which implies that you can easily
> > recreate required mountpoints under /media if you use /etc/fstab
> > as a template).
> This is what I have in /etc/fstab
> # Device Mountpoint FStype Options Dump
> /dev/ada0p2.eli none swap sw 0 0
> /dev/ada1p2.eli none swap sw 0 0
> fdesc /dev/fd fdescfs rw 0 0
> proc /proc procfs rw 0 0
So no entry for da0 - it's valid to conclude that the automounter
you are using will create the appropriate mountpoint in /media
according to the device name, for example /media/da0 or /media/da0s1
or /media/da0p1, depending on partitioning.
> >> At the moment what happens is that upon insertion the 'computer'
> >> browser pane will display a filesystem labelled 'USB Drive' but I
> >> cannot open it for viewing.
> > Is it empty? When you say it's being opened, I assume this is a
> > file browser - but from which desktop? They are quite different!
> I am using the Mate desktop and the file browser application shown as
> 'Computer' on the desktop.
Ah, okay. I've had problems with Gnome 2 and Mate automounter
in the past (permission things), so maybe this is where to
have a closer look.
> > Check things easily: Open a terminal and check the outpuf of
> > % mount -v
> # mount -v
> zroot/ROOT/default on / (zfs, local, noatime, nfsv4acls, fsid
> devfs on /dev (devfs, local, multilabel, fsid 00ff007171000000)
> fdescfs on /dev/fd (fdescfs, fsid 01ff005959000000)
> procfs on /proc (procfs, local, fsid 02ff000202000000)
> zroot/tmp on /tmp (zfs, local, noatime, nosuid, nfsv4acls, fsid
> zroot/usr/home on /usr/home (zfs, local, noatime, nfsv4acls, fsid
> zroot/usr/ports on /usr/ports (zfs, local, noatime, nosuid, nfsv4acls,
> fsid c3353930de6b28f5)
> zroot/usr/src on /usr/src (zfs, local, noatime, nfsv4acls, fsid
> zroot/var/audit on /var/audit (zfs, local, noatime, noexec, nosuid,
> nfsv4acls, fsid 0dde5904de17aec3)
> zroot/var/crash on /var/crash (zfs, local, noatime, noexec, nosuid,
> nfsv4acls, fsid bd542313de5b6740)
> zroot/var/log on /var/log (zfs, local, noatime, noexec, nosuid,
> nfsv4acls, fsid cc095ee9de26f4fd)
> zroot/var/mail on /var/mail (zfs, local, nfsv4acls, fsid
> zroot/var/tmp on /var/tmp (zfs, local, noatime, nosuid, nfsv4acls,
> fsid 1c322eeade9a7a06)
> zroot on /zroot (zfs, local, noatime, nfsv4acls, fsid 521cbba2def75276)
It does not show an entry for /dev/da0<something>, so you can
state that it is _not_ mounted, and the file browser window is
just showing the empty mountpoint directory.
> > Is the USB stick (usually /dev/da0 or /dev/da0s1 or something
> > like that) _really_ mounted?
> Not that I can see. That appears to be the essence of the problem.
Can you _manually_ mount the USB stick? For example, with
% mount -t ext2fs -o ro /dev/da0 /media/da0
No matter if the file browser will automatically open a window for
/media/da0 (in this example), you can check again the output of
% mount -v | grep da0
and of course
% ls /media/da0
to see if the files you are expecting are really there.
> > Check what's on the USB stick, using
> > % gpart show da0
> # gpart show da0
> => 63 122915265 da0 MBR (59G)
> 63 8001 - free - (3.9M)
> 8064 122907264 1 !12 [active] (59G)
Hmmm... that looks really strange... check with "old-fashioned"
% fdisk da0
Is there an ext2 partition? The output you presented looks like
a situation where there's nothing the system can automatically
detect and mount.
(I don't have an ext2 USB stick at hand so I cannot check how
the gpart and fdisk output should look like for a valid TOC with
an ext2 partition.)
Can you re-initialize the USB stick on the Linux system? Just in
case partitioning data has been damaged...
> dmesg shows this:
> ugen3.2: <Kingston> at usbus3
> umass0: <Kingston DataTraveler 2.0, class 0/0, rev 2.00/1.00, addr 2>
> on usbus3
> umass0: SCSI over Bulk-Only; quirks = 0x8100
> umass0:5:0: Attached to scbus5
> da0 at umass-sim0 bus 0 scbus5 target 0 lun 0
> da0: <Kingston DataTraveler 2.0 PMAP> Removable Direct Access SPC-2
> SCSI device
> da0: Serial Number 50E549C20210BF10A9BC4174
> da0: 40.000MB/s transfers
> da0: 60017MB (122915328 512 byte sectors)
> da0: quirks=0x3<NO_SYNC_CACHE,NO_6_BYTE>
Okay, da0 is confirmed, and there are no errors so far.
> >> Neither does a mount command show in the
> >> right-click popup menu.
> > So it probably _is_ mounted. Does the menu show a "detach",
> > "unoumt" or "eject" entry or symbol?
Because it isn't actually mounted, as we can now say for sure.
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...
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