USB storage devices are supported by Red Hat
Enterprise Linux, but a few steps must be taken to make the device
accessible. After plugging in the device, the system logs must be checked
to see how the device was detected. Then the drive must be mounted.
Before removing a USB storage device, it is very important to use the
umount command to flush any buffered data to the device. If the
device is unplugged before this happens, data corruption may occur. Here
are the steps to follow to insert a USB storage device:
Inserting a USB storage device
- Plug in the device.
- Check the contents of the file /var/log/dmesg
to see what the system named the device. (You can use the command
dmesg as well.) It should appear as a SCSI device, so the name
should be similar to /dev/sda or
/dev/sdb.
- Use the command fdisk -l <devicename>
, replacing <devicename> with the
device name from /var/log/dmesg to determine
the partitions on the device. Most USB flash drives and other
portable storage media types have only one partition, so the output
of the fdisk command will most likely be
something like /dev/sda1 or
/dev/sdb1.
- Create a directory (mkdir) to serve as the
drive's mount point. It is recommended to use a name that is easy to
remember like /mnt/usb.
- Mount the device with the mount command.
If the device was detected as /dev/sda and
the fdisk command showed
/dev/sda1 as your partition, the command would be:
mount /dev/sda1 /mnt/usb
The mount command should automatically detect the partition type and
mount the drive. It can be problematic to add the mount command to
the file/etc/fstab, as the device may be
detected with a different name if system devices are changed or if
more than one USB device is plugged in at the same time. For this
reason, it is recommended to mount the device manually with the full
mount command listed above instead of relying on an entry in
/etc/fstab.
Unmounting and removing a USB storage device
It is VERY IMPORTANT to unmount the drive before unplugging it. When the
device is written to, some of the data is cached in system memory and not
immediately written to the device. If the device is unplugged before it
is unmounted, all the data on the device could be corrupted. Please
follow this procedure to unmount and then unplug USB storage devices:
- Close all programs accessing the device or change directories in
these programs to a location not on the USB device. If any programs
are still accessing the device, it will not be possible to unmount
it.
- Issue the command umount /mnt/usb, where
/mnt/usb is the mount point you created in the first set of
directions. Note that the command is called
umount, not unmount. There is no n
in the command name.
- When the umount command completes and the
prompt returns, the storage device can be safely unplugged.
Hi,
A unsupported and highly developmental kernel module is available
which allows a read-only mounting of an NTFS partition. you can check
following kbase for more details on that but it is not recommended.
http://kbase.redhat.com/faq/FAQ_80_4297.shtm
You can format USB hard drive by fdisk utility. before going to the
partitioning issue please take a look at the following kbase article
that talks on howto setup a USB storage device
http://kbase.redhat.com/faq/FAQ_79_4161.shtm
There are kbase available for how to delete partition using
fdisk.
http://kbase.redhat.com/faq/FAQ_43_3866.shtm
How do you use fdisk to add a primary partition?
http://kbase.redhat.com/faq/FAQ_43_3822.shtm
How do I create a new ext3 file system if a disk was added to the
system?
http://kbase.redhat.com/faq/FAQ_80_381.shtm
I would require the sysreport of the system. Sysreport would provide
me the information regarding the disk layout.
Sysreport can be obtained using the following command:
# /usr/sbin/sysreport
Above command will create a tar file in /tmp location. Please attach
the file in reply with this service request.
Please make sure that you have installed the latest sysreport
package. If not please install the latest using the command
up2date -u sysreport
Regards,
Manish Gaikwad