[SOLVED] How to determine why I can't unmount a volume

anon091 · 07-23-2014, 09:32 AM

I have a volume that I thought was only used for some samba shares. All those shares are commented out in smb.conf and samba was restarted, but a umount of that volume tells me the "device is busy" still.

How can I tell what is still using a particular volume?

YankeePride13 · 07-23-2014, 09:55 AM

Are there any users who's current location is on the mounted volume?

anon091 · 07-23-2014, 10:40 AM

just looked in passwd, there are! It's for a couple "service accounts" we have. Guess I need to change those then and see if I can umount then?

anon091 · 07-23-2014, 10:48 AM

OK, just changed their home directories, but I still can't umount. Any other tips on where to check now?

szboardstretcher · 07-23-2014, 10:58 AM

Use lsof to find what is using it:

Code:

lsof | grep sda(or your volume name)

anon091 · 07-23-2014, 11:01 AM

Very cool. When I do a lsof | grep VolumeIWantToUnmount, all I get is this though

bash 15602 MyUserName cwd DIR 8,17 4096 2 /VolumeIWantToUnmount
su 15630 root cwd DIR 8,17 4096 2 /VolumeIWantToUnmount

grim76 · 07-23-2014, 11:09 AM

Looks like you are in the directory that you are trying to unmount. You will want to make sure that you are not in that location as well.

anon091 · 07-23-2014, 11:22 AM

I even just changed to my home directory, which isn't even on the same array as the one I want to unmount, but it's still giving me the same message, and lsof shows the same output.

I even did a who, there's nobody else logged in to the server but me.

szboardstretcher · 07-23-2014, 11:24 AM

Looks like you have used su to become root. Were you on the volume in your pre-su user shell?

Tell you what.

Log out. Completely.
Log back in.
Change to the root directory /
Su to root
Change to the root directory /
Unmount your volume

anon091 · 07-23-2014, 11:34 AM

That's it. and now i'm embarrassed haha. so was it that all along, or was it a combo of that and those users home directories being set to a folder on it? I'm guessing the former

YankeePride13 · 07-23-2014, 11:57 AM

It's cause you were in the mounted volume. That's what I was alluding to in my post, sorry for the confusion.

anon091 · 07-23-2014, 12:01 PM

Looking back, I totally misread your other post. Sorry about that. All is well now, I can mount/umount til the cows come home.

Thanks everybody. Going back to being embarrassed now haha.

Habitual · 07-23-2014, 01:30 PM

Quote:

Originally Posted by rjo98

Looking back, I totally misread your other post. Sorry about that. All is well now, I can mount/umount til the cows come home.

Thanks everybody. Going back to being embarrassed now haha.

No need to be.

Code:

lsof +D /path/to/directory

can show you what's "open" in that directory also.

anon091 · 07-23-2014, 02:38 PM

That's cool. There's so many little commands and options like that you never know exist, until someone points them out.

jpollard · 07-23-2014, 04:02 PM

You can also use the fuser command to look at mount points - it will list all processes that have something open, and tell you how it is being used - each pid is followed by a series of key letters indicating its use:

Code:

              c      current directory.
              e      executable being run.
              f      open file. f is omitted in default display mode.
              F      open file for writing. F is omitted  in  default  display
                     mode.
              r      root directory.
              m      mmap'ed file or shared library.

If no letter is showing, then the process has a file open.