I noticed something similar recently, after setting up a private net.
It turned out that things like sendmail were trying to do a reverse DNS
lookup on my private net, which I had conveniently forgotten to set up.
So it would wait for 10 to 15 seconds on each of 5 retries waiting to
resolve 1.1.16.172.IN-ADDR.ARPA before giving up on it.

Try setting up a reverse-DNS lookup data base, similar to the standard
one that comes in the distribution for 127.IN-ADDR.ARPA

On Thu, 2 Apr 1998, Amitai Schlair wrote:

> I've been having a great time learning UNIX and administration for the
> past few months with NetBSD 1.3. As of late, though, things have been
> getting kind of flaky.
> 
> A couple weeks ago, I noticed that it was starting to take an unusual
> while (30 seconds and up, sometimes several minutes) to access services
> that require authentication (like telnet and qpopper). Sometimes, I
> can't access anything at all; even httpd and the rest take a seat!
> (IPFilter never has trouble, fortunately, else I might have no way of
> sending this message!) As you might suppose, I'm somewhat perturbed by
> this behavior, as the only change I can recall making to the system is
> the addition of an entry for a machine on my private net in /etc/hosts.
> 
> I looked through /etc/gettytab, /etc/ttys, and /etc/inetd.conf, and
> found nothing amiss. Any ideas where the silliness might be originating?
> 
> - Amitai
> 
> -- 
> Nothing is more conducive to peace of mind than not having any opinions
> at all.
>      -- Georg Christoph Lichtenberg
> 

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