A SOA Problem

[Barry Margolin]

In article <g0dis8$2hes$1 at sf1.isc.org>, "?U'?" <desccie at gmail.com> 
wrote:

> hi,all
> 
> I have a SOA problem resolving a domain name.
> 
> [root at redhat ~]# dig @202.96.209.5 sonystyle.com.cn +trace
> 
> ; <<>> DiG 9.2.4 <<>> @202.96.209.5 sonystyle.com.cn +trace
> ;; global options:  printcmd
> .                       444044  IN      NS      g.root-servers.net.
> .                       444044  IN      NS      h.root-servers.net.
> .                       444044  IN      NS      i.root-servers.net.
> .                       444044  IN      NS      j.root-servers.net.
> .                       444044  IN      NS      k.root-servers.net.
> .                       444044  IN      NS      l.root-servers.net.
> .                       444044  IN      NS      m.root-servers.net.
> .                       444044  IN      NS      a.root-servers.net.
> .                       444044  IN      NS      b.root-servers.net.
> .                       444044  IN      NS      c.root-servers.net.
> .                       444044  IN      NS      d.root-servers.net.
> .                       444044  IN      NS      e.root-servers.net.
> .                       444044  IN      NS      f.root-servers.net.
> ;; Received 228 bytes from 202.96.209.5#53(202.96.209.5) in 160 ms
> 
> cn.                     172800  IN      NS      E.DNS.cn.
> cn.                     172800  IN      NS      A.DNS.cn.
> cn.                     172800  IN      NS      B.DNS.cn.
> cn.                     172800  IN      NS      D.DNS.cn.
> cn.                     172800  IN      NS      NS.CERNET.NET.
> cn.                     172800  IN      NS      C.DNS.cn.
> ;; Received 297 bytes from 192.112.36.4#53(g.root-servers.net) in 370 ms
> 
> sonystyle.com.cn.       21600   IN      NS      ns1.sony.com.cn.
> sonystyle.com.cn.       21600   IN      NS      ns2.sony.com.cn.
> ;; Received 107 bytes from 203.119.29.1#53(E.DNS.cn) in 36 ms
> 
> sonystyle.com.cn.       3600    IN      SOA     ns1.sony.com.cn.
> root.sony.com.cn. 2008042218 60 300 172800 3600
> ;; Received 84 bytes from 61.129.39.70#53(ns1.sony.com.cn) in 16 ms
> 
> 
> [root at redhat ~]# dig @202.96.209.5 sonystyle.com.cn
> 
> ; <<>> DiG 9.2.4 <<>> @202.96.209.5 sonystyle.com.cn
> ;; global options:  printcmd
> ;; Got answer:
> ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 36046
> ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0
> 
> ;; QUESTION SECTION:
> ;sonystyle.com.cn.              IN      A
> 
> ;; AUTHORITY SECTION:
> sonystyle.com.cn.       1800    IN      SOA     scnns.sony.com.cn.
> root.scnns.sony.com.cn. 2008042218 60 300 172800 1800
> 
> ;; Query time: 40 msec
> ;; SERVER: 202.96.209.5#53(202.96.209.5)
> ;; WHEN: Fri May 16 12:38:54 2008
> ;; MSG SIZE  rcvd: 86
> 
> [root at redhat ~]# dig @202.106.196.115 sonystyle.com.cn
> 
> ; <<>> DiG 9.2.4 <<>> @202.106.196.115 sonystyle.com.cn
> ;; global options:  printcmd
> ;; Got answer:
> ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 9255
> ;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0
> 
> ;; QUESTION SECTION:
> ;sonystyle.com.cn.              IN      A
> 
> ;; AUTHORITY SECTION:
> sonystyle.com.cn.       1035    IN      SOA     ns2.sony.com.cn.
> root.sony.com.cn. 2008042218 60 300 172800 3600
> 
> ;; Query time: 55 msec
> ;; SERVER: 202.106.196.115#53(202.106.196.115)
> ;; WHEN: Fri May 16 12:40:23 2008
> ;; MSG SIZE  rcvd: 84
> 
> Why the SOA record are different in the above ?

202.96.209.5 is apparently configured as authoritative for the 
sonystyle.com.cn domain (notice the "aa" flag in its answer), so it 
doesn't query the servers that the domain is delegated to.  It has its 
own SOA record, which is different from the one on the official server.

-- 
Barry Margolin, barmar at alum.mit.edu
Arlington, MA
*** PLEASE don't copy me on replies, I'll read them in the group ***