F18 users unable to log in due to cached nsswitch.conf

[Miloslav Trmač]

On Wed, Oct 17, 2012 at 6:29 PM, Stef Walter <stefw at redhat.com> wrote:
> On 10/17/2012 06:21 PM, Miloslav Trmač wrote:
>>
>> That's rather far from actually fixing the problem.  Can we get it
>> fixed_first_?  It seems that we could drop the glibc caching,
>
> Obviously dropping the caching would be pretty nasty. Having to dlopen the
> modules each time you do a getpwnam() (or friends) isn't cool.
>
> I assume you mean fstating the file on each lookup? I'm not against this,
> and I can try and propose this to glibc, but I'm pretty sure what's going to
> happen. See similar /etc/resolv.conf discussions.
Yes, that's basically what I meant (perhaps only on each getXXnam() or
setXXent(), not on sequential getXXent() calls).

>> I'm not opposed to changing the default nsswitch.conf to avoid that
>> reboot (well, I think it's ugly to refer to a non-installed module,
>> but that's an aesthetic, not a principal thing) and to improve the
>> user experience in the default case, but we do need to have some way
>> to fix the underlying problem, a better way than just giving up and
>> conceding that nsswitch.conf can't be edited from now on.
>
>
> We are working on it and I linked to that bug in my report. Ray Strode and I
> are working on patches to glibc.
>
> http://sourceware.org/bugzilla/show_bug.cgi?id=12459

Right, this would still require a modification of every long-running
process dealing with the nsswitch databases.  Modifying the glibc
caching behavior would probably be simpler.

Jeff, what do you think?
   Mirek