Comment 8 for bug 1842037

Hi Matthew,

----- Ursprüngliche Mail -----
> Von: "Bug 1842037" <email address hidden>
> An: "burk" <email address hidden>
> Gesendet: Donnerstag, 26. September 2019 01:27:15
> Betreff: [Bug 1842037] Re: Oops when Kerberos credentials are invalid

> Hi Frank,
>
> Just checking in to see how the test kernel is going. Does it fix your
> problem of the kernel crashing when users have invalid kerberos
> credentials?

I've not been able to reproduce the problem. The suggested method of
triggering it doesn't seem to work because:

   * If there's no kerberos identity (just a local user), the server
     won't let me enter the mounted folder.
   * If the local user is not known network wide but has a Kerberos
     identity and the remote idmapd cannot resolve it, it's mapped to
     nobody on the server.
   * No Oopps in both cases.

> Did you try it on the original server which crashes frequently? Has it
> made things more stable?

I tried on several of the affected servers. They are not more stable but
suffer from different NFS related problems now.

> Did you have an opportunity to try the reproducer I linked you in my
> previous message?
>
> Let me know how things are going, when you have had a chance to test the
> kernel.

NFS is still unstable but the problem seems to be in GSSD now plus in
Bug 1828978 . However, I can't tell you, if 1828978 happens in Xenial, only.
Both problems are triggered relatively seldom and only cause headaches because
they happen on very crowded computer servers. If in doubt, the admins here
try to get the servers running again ASAP which makes analysis very difficult.

However, bug 1842037 is very clearly visible in the logs so I'm quite sure,
I didn't miss it. I think the best solution for now is to park the ticket on
your side and I'll provide feedback as soon as it happens again.

Thank you very much.

Best,

Frank

--
Frank Burkhardt <email address hidden>
IT Dept., Max Planck Institute for Human Cognitive
and Brain Sciences, Leipzig, Germany