Re: 503 Backend fetch failed errors

On 11/8/18 9:19 AM, Magnus Hagander wrote:
>
>
> On Thu, Nov 8, 2018 at 9:01 AM Stefan Kaltenbrunner
> <stefan(at)kaltenbrunner(dot)cc> wrote:
>
> On 11/7/18 6:40 PM, Rémi Zara wrote:
> > Hi,
>
> Hi Rémi!
>
> >
> > I’m getting a lot of these errors with coypu (several per day),
> but not systematically.
> > Is this a problem on my end, or is this on the sever end ?
> >
> > Query for: stage=OK&animal=coypu&ts=1541573277
> > Target:
> https://buildfarm.postgresql.org/cgi-bin/pgstatus.pl/53b137e7c765b781699bbe73e3aec7751a8c4ab7
> > Status Line: 503 Backend fetch failed
> > Web txn failed with status: 1
> > Query for: stage=OK&animal=coypu&ts=1541575423
> > Target:
> https://buildfarm.postgresql.org/cgi-bin/pgstatus.pl/5e8e0913dc9f9a580a4125264d74fff95f26c926
> > Status Line: 503 Backend fetch failed
> > Web txn failed with status: 1
>
> given the error this is something that is created by the varnish
> instance that is in front of the buildfarm. On a quick look I could
> immediately figure out what the problem is - but it looks like you (or
> somebody else) tried at least to click one of the links above using
> hist
> desktop browser and got an error about a missing branch specification ;)
>
>
>
> AFAICT:
>
> A quick look in the logs indicates that the buildfarm is responding:
> -   RespHeader     Status: 492 bad branch parameter
>
> However, 492 is not a valid http status code, so Varnish can't handle it
> and thus returns 503 failure to the client.

I think that is not the actual error that Rémi is experiencing- the 492
case (which is indeed an invalid http error code) only happens when one
actually klicks the link in the mail above(which I guess some did and
you found in the logs) because the actual BF client will add a parameter
to the "Target" URL.

The actual "errors" dont seem to show up in the lighttpd logs afaiks.