Arch Linux

moere

Member

Registered: 2010-02-14

Posts: 29

udev usb pmount, remove -> just pull out?

Hi there,

I use udev.
I use this udev rule for mounting usb devices.
http://wiki.archlinux.org/index.php/Ude … n-mounting

But how do I use the remove feature?

Do I simply pull out the usb device? (The created folder is done after I pull the device out)
But is this the right way? (Is there possible harm to the filesystem or sth on the usb device?)

Thanks in advance.

perbh

Member

From: Republic of Texas

Registered: 2005-03-04

Posts: 765

Re: udev usb pmount, remove -> just pull out?

Well - it's one reason why I _never_ trust udev. Mounting is OK (though _I_ want to be in control), umounting is a different kettle of fish alltogether. The only reason why I can imagine it works is if you force all the writes and don't use cache - in which case any kind of writing will be rather slow :-(

As for recommendation - I certainly would wait awhile before pulling it out - making sure that absolutely _everything_ has been flushed to the drive (which would depend on what other tasks (especially i/o) that you have going.)

Me - I manually umount the sucker when I'm done with it - and I don't want those automounts either as they can end up with something like '/media/12345678-90ab-cdef-1234-567890abcdef' - now how the dickens do you use the CLI on something like that??
Nah, I'm going the 'old' trusted way:
mount  /dev/sdb1  /mnt/usb
# do something
umount  /mnt/usb
- and yes, I'm root doing it (I just l-o-v-e the "POWAH" ( to quote someone else on this forum)) - I have about 8 desktops and one of them have a couple of xterms where I have su'd to root - only using them when I have to (like for mount/umount). To me, that is the 'old' way and I far prefer it to polkit or what have you - xml is verbal diarrhea as far as I'm concerned.

tomk

Forum Fellow

From: Ireland

Registered: 2004-07-21

Posts: 9,839

Re: udev usb pmount, remove -> just pull out?

As you can see in the rule, removing the device will run the pumount command. However, everything perbh said in his first two paragraphs applies. Personally, I run pumount manually, unless I know the device has been unused for a sufficiently long time.

perbh, those rules are written to make use of partition labels, not UUIDs - obviously, the user is expected to apply labels first.

perbh

Member

From: Republic of Texas

Registered: 2005-03-04

Posts: 765

Re: udev usb pmount, remove -> just pull out?

perbh, those rules are written to make use of partition labels, not UUIDs - obviously, the user is expected to apply labels first.

Yeah - I know you're right - I got mixed up with linuxmint for a moment - they use uuid.
Still - labels are not unique (I still hate the way redhat uses '/' for the first root filesystem label, then '/1' for the next etc) - I guess I'm just too old-fashioned. I like the 'old' way the best - but hey, I'm not gonna ram that down anybody's throat - it just works for _me_.

Last edited by perbh (2010-06-11 17:01:10)

tomk

Forum Fellow

From: Ireland

Registered: 2004-07-21

Posts: 9,839

Re: udev usb pmount, remove -> just pull out?

Not sure what you mean there - labels are user-defined, they can be as unique as you want.

moere

Member

Registered: 2010-02-14

Posts: 29

Re: udev usb pmount, remove -> just pull out?

Alright, thx alot.

So I have to wait long enough or I have to unmount it manually.

perbh

Member

From: Republic of Texas

Registered: 2005-03-04

Posts: 765

Re: udev usb pmount, remove -> just pull out?

Not sure what you mean there - labels are user-defined, they can be as unique as you want.

Yes, but usb's are made to move around from one computer to the next. There is no guarantee - if you move it to someone else's computer - that that person hasn't allready mounted a usb-stick with the same label ... or has a nasty script that gets executed if that particular label is encountered ...
And human frailty being what it is - I wonder how many usb's have labels like "my_data" or "my_pics" or anything else equally uniq ...

It's not a big point, though, and I'm not trying to start a flamewar - inasmuch as I refuse to use automount myself, I really should have no vote in the matter - other than possibly explaining _why_ I feel the way I do.