Hi-- On Aug 8, 2011, at 1:15 PM, Mark K. Pettit wrote: > My resolvers, running BIND 9.7.3P3, are having a difficult time resolving the > MX record for the zone "epza.gov.tw.". [ ... ] > But if I query any of [abc].twnic.net.tw. directly for the IP address of > dns.epza.gov.tw, I get an answer. Example: [ ... ] > It appears to me that BIND is seeing this response, and then ignoring the IP > in the Additional section. > > Any idea why this might be happening?
The trace I get here shows: ;; Received 191 bytes from 211.79.207.26#53(e.dns.tw) in 221 ms epza.gov.tw. 43200 IN NS dns.epza.gov.tw. ;; Received 63 bytes from 168.95.192.10#53(c.twnic.net.tw) in 213 ms dig: couldn't get address for 'dns.epza.gov.tw': not found It looks like Google's public nameservers chase a CNAME when you ask for an A record, but I thought nameservers listed in NS records should have a corresponding A record and _not_ a CNAME. Compare versus the level-3 nameservers, which get a SERVFAIL: % dig dns.epza.gov.tw @8.8.8.8 ; <<>> DiG 9.6.0-APPLE-P2 <<>> dns.epza.gov.tw @8.8.8.8 ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 40236 ;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 0 ;; QUESTION SECTION: ;dns.epza.gov.tw. IN A ;; ANSWER SECTION: dns.epza.gov.tw. 3600 IN CNAME ns.epza.gov.tw. ns.epza.gov.tw. 3600 IN A 163.29.43.1 ;; Query time: 439 msec ;; SERVER: 8.8.8.8#53(8.8.8.8) ;; WHEN: Mon Aug 8 16:25:36 2011 ;; MSG SIZE rcvd: 66 % dig dns.epza.gov.tw @4.2.2.1 ; <<>> DiG 9.6.0-APPLE-P2 <<>> dns.epza.gov.tw @4.2.2.1 ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 10484 ;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0 ;; QUESTION SECTION: ;dns.epza.gov.tw. IN A ;; Query time: 11 msec ;; SERVER: 4.2.2.1#53(4.2.2.1) ;; WHEN: Mon Aug 8 16:29:37 2011 ;; MSG SIZE rcvd: 33 Regards, -- -Chuck _______________________________________________ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
