On Sat, Aug 28, 2010 at 11:00 PM, Yaron <tclug at freakzilla.com> wrote:

> On Sat, 28 Aug 2010, Robert Nesius wrote:
>
>  suppose you could ssh into the box and attach a stack tracer to the daemon
>> handling logins and follow forks...  (I haven't tried this, but it could
>> work.)
>>
>
> The SMALL problem with that is I'd have to ssh in as root which is just...
> ewww. But I'd do it on a temporary basis if it'll help solve this.
>
> The bigger problems are A) What daemon do I attach a stack tracer to, and
> B) What the heck is a stack tracer? (ok I assume that's strace or truss or
> ptrace or whatever the Linux equivalent of those is).
>

Right - strace or ktrace or truss or... I think it's just strace on linux.

I should know the answer to question A) but don't off the top of my head.
I'll fire up my virtual machine tomorrow and see what I find. BUT - if you
log in via ssh as a non-root user you could run strace against the su
command.   'strace -f -o /tmp/strace.out su - user'.   You should be
prompted for a password and you should be able to see what system call does
the epic-hang.

-Rob
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