Re: [opensuse] HOWTO: ivman, fixed mount-points and growisofs

That was one of the things I have been tinkering with off and on for the last couple of months. Thanks a lot for this article! Maybe you want to put it in the openSUSE wiki? -- Gruß Andreas Am Dienstag, 6. November 2007 06:15:48 schrieb Frank Steiner:

Hi,

I post a solution we found (partially with the help of the SuSE support) for other people here that may have similar problems, and to be found via archives/Google :-)

Our goals are: -------------- 1) automounter for users without KDE and Gnome 2) fixed mount-points for CDs/DVDs because we don't want to check /media/ for the mountpoint, but always find our DVDs at /media/dvd or /media/cdrecorder. 3) files on mounted DVDs should belong to the user 4) burn DVDs with growisofs as user. 5) Additionally, have an instance of ivman running for root.

Not as simple as it seems ;-)

Our solution: ------------- To use fixed mount points, we define /etc/ivman/IvmConfigActions.xml (all following examples only for the DVD-RW to keep it shorter):

<?xml version="1.0" encoding="UTF-8"?> http://www.eikke.com/ivm">

<!-- perform these rules on devices already attached when Ivman starts -->

<!-- try to mount any mountable volume at all -->

A user should start ivman with "ivman -c /etc/ivman" because there are version of ivman (e.g. in 10.1) that do not copy the global config files correctly to the users homedir.

With this config, ivman will call "halmount /dev/sr1 cdrecorder", thus the files on the DVD mounted will belong to the user.

Note that when having a fstab-entry with "users" and calling "mount" here (that was the first solution...) the files on the mounted DVD will be owned by root. Thus, "600" files are not readable for the user who mounted the DVD :-( That's why we need halmount.

Note that with this config alone, we would have two mounts for every DVD, /media/cdrecorder *and* /media/<label of the dvd>, because ivman calls it's normal mount procedure, too. Defining which can be found in some proposals, is not a good idea if you want a second ivman instance for root, see below. But we don't need it anyway as we see in a moment.

Now, when we call growisofs with the DVD-RW mounted because it already contained a FS, growisofs will complain it cannot unmount the DVD and exit.

We could do it ourself with "halmount -u /dev/sr1", but that's not nice... So we add a line in fstab:

/dev/sr1 /media/cdrecorder auto noauto,users,user

We use noauto to avoid mounting accidentally by "mount -a". growisofs can unmount /dev/sr1 now because of the "users" entry.

However, when halmount finds an fstab entry for a device it tries to mount, it mounts only if it finds the "user" option, so we need "users" and "user" here.

Additionally, halmount refuses to mount the device anywhere else but on the mountpoint defined in /etc/fstab. Thus, calling "halmount /dev/sr1 blabla" will fail! This makes the second mount go away: ivman first tries to call "halmount /dev/sr1" which would end up in /media/<label of dvd>, but in the debug mode we can see

manager.c:786 (ivm_run_command) Running: halmount '/dev/sr1' /dev/sr1: /etc/fstab configuration does not allow this mountpoint

so we finally have only one mount at /media/cdrecorder. For most people we are finished here, but we still have goal 5). I sometimes use PCs where no one is logged in for burning DVDs if we have a lot to burn and let ivman start automatically when I log in as root, because I often burn root-only-readable files. Such an root-ivman instance could still be running when a user logs in.

Now when a user-ivman and a root-ivman are running in parallel, the root-ivman could win on mounting DVDs, making files on it be owned by root and unreadable by users. To avoid this, ivman has a sleep option that makes ivman instances started by root or with -s sleep for 5 seconds. Due to this delay, a user-ivman will win. But, when setting the "mount" option to "false" as found in some proposals for fixed mount-points, this sleep is deactivated, too, and a left-over ivman instance by root could disturb the user instance. However, as seen above, we don't need to set "mount" to false to avoid double mounts, so with the configs above we can just have user- and root-instances of ivman running in parallel.

Maybe this helps some people with similar needs :-)

cu, Frank

-- Dipl.-Inform. Frank Steiner Web: http://www.bio.ifi.lmu.de/~steiner/ Lehrstuhl f. Bioinformatik Mail: http://www.bio.ifi.lmu.de/~steiner/m/ LMU, Amalienstr. 17 Phone: +49 89 2180-4049 80333 Muenchen, Germany Fax: +49 89 2180-99-4049 * Rekursion kann man erst verstehen, wenn man Rekursion verstanden hat. * -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org