Forwarders under 8.2.2-P5 slightly broken?

[Kevin Darcy]

This looks like a timing issue with the forwarder. On the first query, it's
getting the NS records, but not the A record. When the query is repeated, it
now has less work to do to resolve the query (in fact the response to the
A record query may have been received in the interim), so it returns an answer
before the client times out. Either your Internet connection is very
slow/congested, or there's something wrong with the configuration of the
forwarder or some device in between it and the Internet. I'd check the
forwarders hints file, and if that looks OK, turn on debugging to see what's
actually happening in that nameserver when it tries to resolve these names.


- Kevin

Bruno Hall wrote:

> Greetings,
>
> I've got a couple machines running 8.2.2-P5 on RedHat Linux 6.2 (2.2.16-3).
>
> The first machine has been configured to forward all requests to
> the second one, as in:
>
> options {
>         forwarders { ip.of.second.machine; };
>         forward only;
> };
>
> The second machine is has root hints.
>
> The problem I've noticed is that about 50% of the time, when a query
> is sent to the first machine, it times out.  When the same query is
> immediately sent again, it succeeds.  After the first query, there is
> nothing regarind the query in the cache of the first machine.  Meanwhile,
> on the second machine, after the first query is sent, the cache contains
> the NS records for the domain containing the RR sought, but not the RR
> in question.
>
> Example:
>
> % dig @localhost www.gnac.com a
>
> ; <<>> DiG 8.2 <<>> @localhost www.gnac.com a
> ; (1 server found)
> ;; res options: init recurs defnam dnsrch
> ;; res_nsend to server localhost  127.0.0.1: Connection timed out
>
> % dig @localhost www.gnac.com a
>
> ; <<>> DiG 8.2 <<>> @localhost www.gnac.com a
> ; (1 server found)
> ;; res options: init recurs defnam dnsrch
> ;; got answer:
> ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 6
> ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 2
> ;; QUERY SECTION:
> ;;      www.gnac.com, type = A, class = IN
>
> ;; ANSWER SECTION:
> www.gnac.com.    28m45s IN A    198.151.248.248
>
> ;; AUTHORITY SECTION:
> gnac.com.        28m45s IN NS   ns1.gnac.com.
> gnac.com.        28m45s IN NS   ns2.gnac.net.
>
> ;; ADDITIONAL SECTION:
> ns1.gnac.com.    28m45s IN A    209.182.195.77
> ns2.gnac.net.    28m45s IN A    198.151.248.183
>
> ;; Total query time: 20 msec
> ;; FROM: first.domain.com to SERVER: localhost  127.0.0.1
> ;; WHEN: Thu Jul 20 19:10:49 2000
> ;; MSG SIZE  sent: 30  rcvd: 130
>
> What am I missing?
>
> Bruno
> --
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