Slow DNS and reloading

Russ Allbery rra at
Thu Apr 18 19:19:01 UTC 2002

Jeffrey M Vinocur <jeff at> writes:

> I just tried `ctlinnd reload incoming.conf` and it just sat there.  I
> thought innd had crashed at first, but it hadn't.  It just wasn't
> responding.

> Attaching with gdb I realized that it was waiting for some DNS lookups
> to timeout.  (I guess I should prune my incoming.conf, eh?)  A couple
> minutes later everything returned to normal.

> It's probably not worth doing anything about this, but it was 
> disconcerting enough that I thought I'd mention it.

Yup, always happens that way.  INN uses gethostbyname, which goes off and
does its work and returns when it feels like it, which can be some time

The long-term solution is to do the same thing that Netscape on Unix does
and fork off a separate process just to do DNS lookups so that they can be
done asychronously, but that's a good bit of work.

Russ Allbery (rra at             <>

    Please send questions to the list rather than mailing me directly.
     <> explains why.

More information about the inn-workers mailing list