dconf doesn't support NFS

[Marc Gariépy]

Description: Ubuntu maverick (development branch)
Release: 10.10

apt-cache policy empathy
empathy:
  Installed: 2.31.92-0ubuntu2
  Candidate: 2.31.92-0ubuntu2
  Version table:
 *** 2.31.92-0ubuntu2 0
        500 http://archive.ubuntu.com/ubuntu/ maverick/main amd64 Packages
        100 /var/lib/dpkg/status

apt-cache policy libdconf0
libdconf0:
  Installed: 0.5-1ubuntu5
  Candidate: 0.5-1ubuntu5
  Version table:
 *** 0.5-1ubuntu5 0
        500 http://archive.ubuntu.com/ubuntu/ maverick/main amd64 Packages
        100 /var/lib/dpkg/status

I have a lot of .nfs* in the .config/dconf/ directory
user1@host:~/.config/dconf$ ls -las
total 20
4 drwx------ 2 user1 group1 4096 2010-09-22 14:18 .
4 drwxr-xr-x 14 user1 group1 4096 2010-09-22 14:18 ..
4 -rw-r--r-- 1 user1 group1 696 2010-09-22 14:18 .nfs000000000522b75f000002c6
4 -rw-r--r-- 1 user1 group1 696 2010-09-22 13:57 .nfs000000000522b76f000002c5
4 -rw-r--r-- 1 user1 group1 696 2010-09-22 14:18 user

When using a user with the home directory outside of the nfs server, everything is working as expected.

[Alexander Betaev (infestator)]

Have the same problem.
I have noticed that dconf creates a tcp connection to my NFSv4 server. May it be useful?

[Liam O'Reilly (aliam13-2)]

I have the same issue with Ubuntu 10.10 64 bit. Could other programs be affected by this?

[Alexander Betaev (infestator)]

As I understand, all programs which use dconf (new configuration API) instead of gconf (the old one) are affected. For now I had found that Empathy and Evince use dconf. Evince crashes every time I try to launch it. But there were some successful launches when it told me that it could not connect to dconf service.

[Trois Singes (trois-singes)]

I confirm : I have the same issue with Ubuntu 10.10 32 bits.

[Valentijn Sessink (valentijn)]

http://ubuntuforums.org/showthread.php?t=1646526 seems to suggest that this is Inotify-related. That would mean that this is another manifestation of the problem described in Bug #383118 (which is, in it's own, a bit misguided as it's probably not Gamin, but the kernel that is at fault, but I'm not sure).

[Wapsi (miikka-veijonen)]

Hi,

I confirm this bug too. With NFSv3 or NFSv4 preferences don't get saved properly in Empathy or in Evince (or in any program using dconf instead of gconf?).

When I run Evince I'll get this error message (/home -directory is mounted over nfs):
** (evince:19067): CRITICAL **: Unable to contact dconf service
...and when I try to open file browser dialog in Evince the program freezes.

BTW:
There is no this problem when I mount /home over network with GlusterFS or MooseFS.

[Alexander Barton (alex-barton)]

I'm seeing this as well, renders Empathy quite useless for me :-(
Are there no workarounds possible? Linking the dconf datastore to a local file system or something like that?

[Wapsi (miikka-veijonen)]

Has anybody tested this with Ubuntu Maverick (11.04)?

I tested couple weeks ago and there weren't those "Unable to contact dconf service" errors, but something else. I have to test and analyze it again when I have time.

[Wapsi (miikka-veijonen)]

I meant Ubuntu Natty 11.04 of course.

[müzso (bit2)]

Confirmed on Ubuntu 10.10 using NFSv3 on /home.

[derlinuxer (derlinuxer)]

Hi,

have same problem with NFS and dconf and found a workaround in connection with empathy.

change the CACHE Path to a non nfs mount area and the start empathy.

like:
export XDG_CACHE_HOME=/export/nonNFS
empathy

OK this will not solve the bug.
I guess the problem is that dconf will do something in the "cache dir" (inside the NFS mount
filesystem) with root rights. If the option no_root_squash is set on the NFS Server for this export it will be denied.

default XDG_CACHE_HOME is $HOME/.cache

derlinuxer

[Wapsi (miikka-veijonen)]

Hi,

Greetings from Finland!

I installed Ubuntu Natty 11.04 Alpha 3 (virtually) and mounted /home over NFSv4 (+NIS) (with same options that I've used a long time). I didn't get any dconf related errors at all. Everything (Empathy and Evince) worked like they should.

Maybe you should try Ubuntu 11.04 too and confirm that this bug is gone in Ubuntu 11.04... Hopefully.

BR,
Wapsi

[Trois Singes (trois-singes)]

Hi,

Maybe it works in Ubuntu 11.04. I don't know. But does it mean that it won't be corrected in Ubuntu 10.10 ? It's a quite annoying bug, with no workaround AFAIK.

Regards.

[derlinuxer (derlinuxer)]

Hi Wapsi,

can you paste the nfs export option from server for the home directory?
NFS exports are set in /etc/exports on the server.
e.g. /mnt/raid 10.10.0.0/16(rw,sync,nohide,root_squash)

I also will try 11.04 in the next days.

thanks

derlinuxer

[Wapsi (miikka-veijonen)]

Hi,

my (export) options in the server is (NFSv4):
/export/home x.x.x.x/24(rw,async,no_subtree_check,nohide,root_squash)

and NFS clients have this in fstab:
hostname:/home /home nfs4 rsize=32768,wsize=32768,rw,hard,user,noatime,udp,intr,exec,nosuid,async,nodev,noauto 0 0

BTW.
I pasted my temporary fix for this issue to the Ubuntu's forum. Here is link: http://ubuntuforums.org/showpost.php?p=10571022&postcount=14

[derlinuxer (derlinuxer)]

Hi Wapsi and all others,

thanks for your NFS infos.

I also run a test with Ubuntu 11.04Beta and yes it's working without any workaround.

dconf pack version Ubuntu 10.10 -> 0.5-1ubuntu6
dconf pack version Ubuntu 11.04 -> 0.7.3ubuntu1

I didn't found a direct point in change log between this versions, but there are a log changes of course (on backend too).

This is not a proof of fix this issue but I guess a good hope. ;-}

derlinuxer