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sneakyimp 07-13-2010 08:25 PM

DNS fail: can't resolve subdomains, server giving wrong response
 
I've got a DNS problem I cannot figure out. I've been digging and pinging all day and I've waited for caches to expire and I'm not having much luck. Any help would be much appreciated.

From my desktop mac, I can't seem to resolve mail.port-o-call.net:
Code:

My-Mac:~ sneakyimp$ ping mail.port-o-call.net
ping: cannot resolve mail.port-o-call.net: Unknown host

whereas port-o-call.net resolves just fine:
Code:

My-Mac:~ sneakyimp$ ping port-o-call.net
PING port-o-call.net (67.14.192.54): 56 data bytes
64 bytes from 67.14.192.54: icmp_seq=0 ttl=50 time=74.573 ms
64 bytes from 67.14.192.54: icmp_seq=1 ttl=50 time=85.275 ms

Curiously, I can dig port-o-call.net and get a very reasonable output:
Code:

My-Mac:~ sneakyimp$ dig port-o-call.net

; <<>> DiG 9.4.3-P3 <<>> port-o-call.net
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 57523
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;port-o-call.net.              IN      A

;; ANSWER SECTION:
port-o-call.net.        604517  IN      A      67.14.192.54

;; Query time: 97 msec
;; SERVER: 192.168.1.1#53(192.168.1.1)
;; WHEN: Tue Jul 13 17:16:12 2010
;; MSG SIZE  rcvd: 49

But when I dig mail.port-o-call.net, I get some info that i know is outdated and which lacks an ANSWER section.
Code:

My-Mac:~ sneakyimp$ dig mail.port-o-call.net

; <<>> DiG 9.4.3-P3 <<>> mail.port-o-call.net
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 7671
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:
;mail.port-o-call.net.          IN      A

;; AUTHORITY SECTION:
port-o-call.net.        10471  IN      SOA    ns2.radicalcomputingconcepts.com. keystone.peardrax.cei.net. 2010071301 28800 7200 604800 39600

;; Query time: 103 msec
;; SERVER: 192.168.1.1#53(192.168.1.1)
;; WHEN: Tue Jul 13 17:17:21 2010
;; MSG SIZE  rcvd: 128

Am I correct in thinking that the previous response would result in a query to the servers in the SOA record? If so, I get this from ns2.radicalcomputingconcepts.com:
Code:

My-Mac:~ sneakyimp$ dig @ns2.radicalcomputingconcepts.com mail.port-o-call.net

; <<>> DiG 9.4.3-P3 <<>> @ns2.radicalcomputingconcepts.com mail.port-o-call.net
; (1 server found)
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 37351
;; flags: qr aa rd; QUERY: 1, ANSWER: 2, AUTHORITY: 2, ADDITIONAL: 2
;; WARNING: recursion requested but not available

;; QUESTION SECTION:
;mail.port-o-call.net.          IN      A

;; ANSWER SECTION:
mail.port-o-call.net.  600    IN      A      67.14.192.54
mail.port-o-call.net.  600    IN      A      67.14.192.54

;; AUTHORITY SECTION:
port-o-call.net.        259200  IN      NS      ns1.radicalcomputingconcepts.com.
port-o-call.net.        259200  IN      NS      ns2.radicalcomputingconcepts.com.

;; ADDITIONAL SECTION:
ns1.radicalcomputingconcepts.com. 259200 IN A  67.14.192.56
ns2.radicalcomputingconcepts.com. 259200 IN A  66.55.47.207

;; Query time: 68 msec
;; SERVER: 66.55.47.207#53(66.55.47.207)
;; WHEN: Tue Jul 13 17:21:33 2010
;; MSG SIZE  rcvd: 166


Question 2: Where is this response coming from?
I can't help but wonder where this response comes from, because ns2 has a different answer and the server at cei.net doesn't exist. Why is there no answer section?
Code:

My-Mac:~ sneakyimp$ dig mail.port-o-call.net

; <<>> DiG 9.4.3-P3 <<>> mail.port-o-call.net
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 7671
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:
;mail.port-o-call.net.          IN      A

;; AUTHORITY SECTION:
port-o-call.net.        10471  IN      SOA    ns2.radicalcomputingconcepts.com. keystone.peardrax.cei.net. 2010071301 28800 7200 604800 39600

;; Query time: 103 msec
;; SERVER: 192.168.1.1#53(192.168.1.1)
;; WHEN: Tue Jul 13 17:17:21 2010
;; MSG SIZE  rcvd: 128


jma89 07-13-2010 10:52 PM

I'm able to resolve mail.port-o-call.net when I tell host to use ns2.radicalcomputingconcepts.com

Code:

johnsmacbook:~ john$ host mail.port-o-call.net ns2.radicalcomputingconcepts.com
Using domain server:
Name: ns2.radicalcomputingconcepts.com
Address: 66.55.47.207#53
Aliases:

mail.port-o-call.net has address 67.14.192.54
mail.port-o-call.net has address 67.14.192.54

Perhaps it's worth a deeper check into your DNS server's setup or a call to their IT dept?

sneakyimp 07-14-2010 01:45 AM

Thanks for your response.

I agree that ns2.radicalcomputingconcepts.com seems to return the correct response for mail.port-o-call.net, however ns2 doesn't appear to be the providing the definitive answers to my mac here. ns2 is listed as SOA for mail.port-o-call.net:
Code:

My-Mac:~ sneakyimp$ dig mail.port-o-call.net

; <<>> DiG 9.4.3-P3 <<>> mail.port-o-call.net
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 42141
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:
;mail.port-o-call.net.          IN      A

;; AUTHORITY SECTION:
port-o-call.net.        10415  IN      SOA    ns2.radicalcomputingconcepts.com. keystone.peardrax.cei.net. 2010071301 28800 7200 604800 39600

;; Query time: 91 msec
;; SERVER: 192.168.1.1#53(192.168.1.1)
;; WHEN: Tue Jul 13 22:41:29 2010
;; MSG SIZE  rcvd: 128

However, try this:
Code:

My-Mac:~ sneakyimp$ host mail.port-o-call.net
Host mail.port-o-call.net not found: 3(NXDOMAIN)

Or this:
Code:

My-Mac:~ sneakyimp$ ping mail.port-o-call.net
ping: cannot resolve mail.port-o-call.net: Unknown host

wtf?

Manuel-H 07-14-2010 02:47 AM

What is your entry for /etc/resolv.conf ?

try putting this two lines as the first 2 nameserver
nameserver 67.14.192.56
nameserver 66.55.47.207

sneakyimp 07-14-2010 01:24 PM

Thanks for your response Manuel-H.

Which machine are you talking about? There's my Mac, ns2.radicalcomputingconcepts.com, mail.port-o-call.net, etc.


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