Strange behavior with RH6.2 and caching-nameserver

[Kevin Darcy]

Well, the first step is to see if the queries are even getting to your
DNS server. Turn on query logging or use a sniffer/packet-tracer. Assuming
that they are, are answers being sent back before the client times out? If
so, what are the contents of those responses? Packet traces should be able
to reveal all of this.


- Kevin

jw2357 at my-deja.com wrote:

> Hello.
>
> I'm running a standard RH 6.2 with bind-8.2.2_P5-9 and caching-
> nameserver-6.2-2 packages installed. I'm also running linuxconf 1.19r2,
> but haven't used it to change any bind settings. I have the Linux
> machine configured as DNS/firewall (with the connection to the
> Internet) and two Windows 98 machines accessing the Internet through it.
>
> I brought the machine up about 8 days ago and everything was working
> fine until today. My problem is:
>
> 1) Suddenly, the Windows machines can no longer look up a handful of
> sites. I probably wouldn't have even noticed it except that one of the
> sites is my SMTP server. :-( The Windows machines fail with an "unknown
> host" message for these sites. DNS lookup was working for these exact
> same sites just a few days ago.
>
> 2) On the Linux box itself, nslookup works just fine for the same
> sites. In other words, I can lookup the host on the Linux box, but from
> the Windows machines the lookup fails.
>
> 3) The problem only seems to affect a handful of sites, and only from
> the Windows machines.
>
> I have repeatedly rebooted the Windows machines, but that has not fixed
> the problem. I have "soft restarted" named with "killall -HUP", but
> that doesn't fix the problem either.
>
> >From the linux box:
>
> # nslookup pop-server.wi.rr.com
> Server:  mkesms2.wi.rr.com
> Address:  24.160.227.33
>
> Name:    pop-server.wi.rr.com
> Addresses:  24.94.163.172, 24.94.163.171
>
> # nslookup smtp-server.wi.rr.com
> Server:  mkesms2.wi.rr.com
> Address:  24.160.227.33
>
> Name:    smtp-server.wi.rr.com
> Addresses:  24.94.163.171, 24.94.163.172
>
> And from one of the Windows machines:
>
> C:\>ping pop-server.wi.rr.com
>
> Pinging pop-server.wi.rr.com [24.94.163.171] with 32 bytes of data:
>
> Reply from 24.94.163.171: bytes=32 time=57ms TTL=113
> Reply from 24.94.163.171: bytes=32 time=56ms TTL=113
> Reply from 24.94.163.171: bytes=32 time=53ms TTL=113
> Reply from 24.94.163.171: bytes=32 time=52ms TTL=113
>
> Ping statistics for 24.94.163.171:
>     Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
> Approximate round trip times in milli-seconds:
>     Minimum = 52ms, Maximum =  57ms, Average =  54ms
>
> C:\>ping smtp-server.wi.rr.com
> Unknown host smtp-server.wi.rr.com.
>
> Any ideas or suggestions? I am testing the Linux box right now, but
> will need it to be reliable in a production environment so "reboot it
> and see if it goes away" is not an acceptable answer for the Linux box.
>
> Sent via Deja.com http://www.deja.com/
> Before you buy.