[OpenAFS] Check free space on AFS share before login

Stephan Wiesand stephan.wiesand@desy.de
Thu, 2 Feb 2017 09:43:14 +0100

> On 2 Feb 2017, at 08:37, Richter, Michael <m.richter@tu-berlin.de> =
> And the output will be shown in LightDM? I'll give that a try.

Better yet, something like this just works as one would hope:

echo WARNING: Your home directory is almost full.
echo Hit Enter to try to log in, but it may fail.
echo If it does, press Ctrl-Alt-F2, log in on the
echo text screen and free some space. Then log out
echo and press Alt-F7 to get back here.
exit 0

- Stephan

> -----Urspr=C4=82=C5=BAngliche Nachricht-----
> Von: Stephan Wiesand [mailto:stephan.wiesand@desy.de]=20
> Gesendet: Mittwoch, 1. Februar 2017 13:08
> An: openafs-info@openafs.org
> Cc: Richter, Michael
> Betreff: Re: [OpenAFS] Check free space on AFS share before login
> Hi Michael,
>> On 1 Feb 2017, at 11:08, Richter, Michael <m.richter@tu-berlin.de> =
>> Hi,
>> we are using  OpenAFS for the home drive. /home/users is a symlink to =
the AFS path with all the home shares. The users home is for example =
>> The users only have 1 GB of space available in that share. It often =
happens that the quota is reached and they are unable to login. Ubuntu =
doesn=C3=A2=C2=80=C2=99t give a meaningful error message. I think, =
Ubuntu doesn=C3=A2=C2=80=C2=99t know what=C3=A2=C2=80=C2=99s the =
problem, because it sees only =C3=A2=C2=80=C2=9C/=C3=A2=C2=80=C2=9D as =
mountpoint, which has enough free space available.
>> Is there a way to check the free space of the user on login and give =
the user a good error message if there is not enough free space =
available in the AFS share?
> nice idea... I should probably implement that here. Something like
> auth required pam_exec.so stdout /bin/check_home_space
> should work well enough at least with lightdm. Just make the script =
print a short message to stdout and exit 1 in the failure case.
> Hth
> 	Stephan
>> I think about using pam-script to run a script that checks it but I =
can=C3=A2=C2=80=C2=99t see a way to bring back that message to the user. =
Also pam-afs-session seems not to have some option for that. Is there =
some other solution?
>> Greetings
>> Michael

Stephan Wiesand
Platanenallee 6
15738 Zeuthen, Germany