bug#41429: Shepherd Sometimes Crashes

[Katherine Cox-Buday <cox.katherine.e@gmail.com>]

Efraim Flashner <efraim@flashner.co.il> writes:

> On Wed, May 20, 2020 at 09:59:03PM -0500, Katherine Cox-Buday wrote:
>> I am running shepherd as a userspace service manager on an alien distro.
>> Occassionally (often enough as to cause concern), Shepherd is crashing.
>> I am unable to narrow down a cause, but anecdotally, it seems to happen
>> more often when a service it's managing fails repeatedly and is
>> disabled.
>> 
>> I'm running `strace` against the Shepherd process in an attempt to
>> submit a better bug report, but this is all I have for now. Maybe others
>> have also seen this behavior.
>
> I found it happens less often with shepherd-0.8. What version are you
> running? Also possibly related, do you have mismatched versions of guile
> between guix packages and your distro's native packages?

Sorry, I forgot to include the version! I am running 0.8 from a store
which I update ~1 week.

> I've also sometimes found shepherd to crash when I add a service where
> the start command is "wrong", as though the error were so bad that
> shepherd says "Nope! That's it! I quit!"

I'm doing very standard things with `make-forkexec-constructor`, so I
wouldn't expect any problems there.

Your comment is kind of scary though! Shepherd is the thing I want to
stay up no matter what since it's responsible for monitoring and
restarting things. The idea that a misbehaving or poorly written service
could bring down the entire Shepherd process is a problem! Is there no
isolation?

> I'd suggest looking at .config/shepherd/shepherd.log but it's rather
> sparse. Still, it might have something useful.

Yes, this is the first place I looked, but unfortunately there wasn't
much usable informatino.

-- 
Katherine