USB mass storage and mount points

oscarBravo

I wonder if there's a way around this:

I have two USB mass storage devices - a 128MB disgo Lite and a Fuji camera. When I plug either into any USB port, it presents on /dev/sda. I want to use nice friendly mount points, so I have these lines in /etc/fstab:

/dev/sda1     /disgo        vfat       noauto,user    0 0
/dev/sda1     /camera       vfat       noauto,user    0 0

Problem is, this doesn't allow me to use both devices at the same time. If one is already plugged in, plugging the other in makes it present on /dev/sdb instead. I can get around it with sudo mount -tvfat /dev/sdb1 /camera, but it's not nearly as handy as mount /camera.

Is there a way of getting hotplug to recognise the device, and assign it to a predetermined device? Alternatively, does anyone know how to go about writing a script that hotplug can call, so I can automagically mount the device to the appropriate mount point depending on the device type?

slartibardfast

its a job for udev, just write a rule for both of your devices!

here is a nice gentoo guide, should give you enough pointers for what ever flavour you like.

http://webpages.charter.net/decibelshelp/LinuxHelp_UDEVPrimer.html

Best of luck,

maxheadroom

You can do this, but only if you're using UDEV instead of DevFS. You write a custom UDEV rule that assigns your camera to /dev/camera and your usb stick to /dev/disgo

EDIT: Damn, slarti beat me to it

oscarBravo

...and this, my friends, is why I love boards.ie. Three hours later, and I have a customised udev setup consistently creating /dev/ symlinks exactly where I want them.

Thanks, guys.

tomk

Nice one folks. I was about to post about the same issue, and I 've been looking for an excuse to try udev, now that my 2.6 setup is up and running.

I'll be doing it on Debian, so if there are any peculiarities, I'll post them.

dubhthach

My memory is a bit hazy as i tend to use IRIX instead of Linux these days but i always remember under redhat/fedora that with disgo devices that they would appear under /mount once you pluged them in.

maxheadroom

Originally posted by dubhthach
My memory is a bit hazy as i tend to use IRIX instead of Linux these days but i always remember under redhat/fedora that with disgo devices that they would appear under /mount once you pluged them in.

Yes, but the problem is that if you have 2 removable devices, the device names depend on the order they're plugged in (first one gets /dev/sda, second gets /dev/sdb, etc). UDEV lets you do things like "If USB mass storage device with vedor id FUJI and SERIAL NO XXXXX is plugged in, call it /dev/fuji"

Which means that if you mount /dev/fuji as /mount/fuji, you know that its only ever going to be your camera.

quarryman

i've a question to tag onto this.

I have my USB stick working in my unix system but it seems to prevent long filenames. anything longer than 8 chars i think.

it renames longfilename.txt to long~1.txt etc.

any suggestions?

oscarBravo

Originally posted by quarryman
I have my USB stick working in my unix system but it seems to prevent long filenames. anything longer than 8 chars i think.

it renames longfilename.txt to long~1.txt etc.

Check the fstype you're using to mount it - you need vfat. If fstab has auto as the fstype, it will use the first one that works, which is fat16 (I think). Look at my first post for example fstab entries that work, long filenames and all.

maxheadroom

look in /etc/fstab, find the mount point, and change the filesystem from auto or fat to vfat