[Tfug] USB Drives

[Jim Secan]

Still having problems with USB drives, and I think part of the problem
might be in how they're being mounted.  A visiting sysadmin set my system
up (FC3) with a single USB drive that I use for backups.  I have multiple
drives that I rotate daily and run a backup every night.  This has a
hard-wired entry in fstab as follows:

/dev/sda1     /mnt/usbhd    ext3    noauto,defaults 0 0

I then had a data-loaded USB drive mailed to me that I attached to a second
USB port.  This drive was automatically entered into fstab (by fstab-sync?)
to be mounted as /dev/sdb1 at /media/usbdisk.  I don't have the fstab entry
(the drive is removed from the system until I sort things out), but a
"mount" command run while it was connected provided the following:

/dev/sdb1 on /media/usbdisk type ext3 (rw,nosuid,nodev,user=jim)

Not only did the data drive have serious problems (which are still not
resolved), but when the backup tried to run when both drives were attached
to the system IT hung up with similar problems.  When I removed the data
drive, the backup ran without problems.

Now, some questions:

1.  Should I make a hardwired entry for the second drive similar to how the
backup disk is handled rather than let the system handle it automatically?
If so, what device should I be using?

2.  How does the system "know" at what device a USB drive will show up, or
does it?  Is the same device always attached to the same physical USB port?
 If so, how do you determine what device will be assigned to which USB port?

3.  How would problems on one USB drive cause problems on another?

4.  Is there any good guidance available anywhere about handling USB drives
in Linux?  I've done some googling and wasted some time on the FC and RH
sites with little success.

TIA
Jim
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| Jim Secan           | Northwest Research Assoc, Inc |
| (jim at nwra.com)      | 2455 E. Speedway, Suite 204   |
| (520) 319-7773      | Tucson, Arizona 85719         |
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