Safely remove usb disks/drives

rahilrai · 03-21-2006, 11:10 PM

How to Safely remove usb disks/drives

Hi, every time i plig in a usb drive (ipod included) it is automounted and a nice icon shows up on the desktop. So far so good.

My problems start when i right click on any of the usb drive icons and click on remove. It gives an error "cannot unmount" or something like that.

Can somebody shed some light on this. Is it harmful to directly unplug the usb drive from the system?

Thx in advance

abisko00 · 03-22-2006, 02:41 AM

"cannot unmount" usually appears when the device is still in use. "Use" can mean that you still have a konqueror window open, that shows the content of the drive. Close all applications that may access the drive and try again. On the other hand, since sync is used (see your other thread) it should be safe to remove the drive anyway.

archtoad6 · 03-26-2006, 04:52 AM

Code:

lsof  | less -S~#22

can be helpful in finding which app. that is.

EclipseAgent · 03-26-2006, 11:06 AM

Are you trying to unmount as root or regular user?

Korto · 03-26-2006, 03:13 PM

Code:

eject /dev/sda1

works fine for me. The stick may not be sda1, but

Code:

eject /dev/sdaX

should work

archtoad6 · 03-27-2006, 07:27 AM

All well & good, & eject is a good cmd. to know; but we are not addressing the fact that you can't eject a device if it's busy, even root may not be able to u(n)mount it. Even:

Code:

# umount -f /mnt/cdrom

doesn't work. (The "#" is the root prompt.)

The real Q is: HTF are we supposed to figure out which is the "offending" app. when umount refuses to work & gives a less-than-helpful "device is busy" msg.? Here are some code suggestions:

Code:

DEV=<device_you_are_trying_to_eject>
kill `lsof  | grep $DEV  | awk '{print $2}'`

This works for me, on my cdrom, w/ 2 instances on Konqueror open displaying its contents. I did not test it further. YMMV.

It would be nice if umount had an option to list the apps./open files that are blocking the command. It would be even nicer if umount had an option to close apps./open files & "just do it".

It would be nice if eject had a force option that would incorporate the above.

We shouldn't be having to have this discussion.

zba78 · 03-27-2006, 07:36 AM

With regards to USB drives, I didn’t think the user had to unmount/eject them. When I’m done with the USB stick I just unplug it and it automatically unmounts it without ever giving any trouble.

I though that was the whole point of automounting!

archtoad6 · 03-27-2006, 03:38 PM

Even in "Winders" you must formally close the open files & "eject" the thumb drive to avoid possible file system corruption.