Unexpected RCODE (15)

[Simon Waters]

> Can you give the circumstances under which you get this RCODE?

Ah -- I can reproduce it with this.

 dig +norec @212.20.0.126 l23.iae.nsk.su a     
Which gives a status "RESERVED15" which I assume is the problem RCODE.

Claimed BIND
VERSION.BIND.           0       CH      TXT     "8.4.5-REL"


Some of the other servers I am seeing similar from are doing so indirectly I 
think. i.e. They have cached or changed state for the recode in some way from 
a server that returned it as above.

Thus I can force the result for the dns2.gaoland.net server I see, by issuing 
a recursive query for the logged record to the logged server, and then 
issuing the same query with "+norec" immediately afterwards. 

Thus from:

Jul 21 11:19:00 localhost named[5057]: unexpected RCODE (15) 
resolving 'achema.com/A/IN': 195.22.175.1#53

Okay so I issue the query I think my DNS may have issued (well one similar).

$ dig @195.22.175.1  +norec achema.com a

; <<>> DiG 9.3.4-P1.1 <<>> @195.22.175.1 +norec achema.com a
; (1 server found)
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 223
;; flags: qr ra; QUERY: 1, ANSWER: 0, AUTHORITY: 2, ADDITIONAL: 2

;; QUESTION SECTION:
;achema.com.                    IN      A

;; AUTHORITY SECTION:
achema.com.             7190    IN      NS      ns1.omnitel.net.
achema.com.             7190    IN      NS      ns2.omnitel.net.

;; ADDITIONAL SECTION:
ns1.omnitel.net.        86400   IN      A       194.176.32.129
ns2.omnitel.net.        86400   IN      A       195.22.175.1

;; Query time: 63 msec
;; SERVER: 195.22.175.1#53(195.22.175.1)
;; WHEN: Mon Jul 21 14:26:08 2008
;; MSG SIZE  rcvd: 107

Immediately repeat without the "+norec" flag.

$ dig @195.22.175.1   achema.com a

; <<>> DiG 9.3.4-P1.1 <<>> @195.22.175.1 achema.com a
; (1 server found)
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 52533
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:
;achema.com.                    IN      A

;; AUTHORITY SECTION:
achema.com.             10800   IN      SOA     ns1.omnitel.net. 
hostmaster\@omnitel.net. 2008041003 28800 7200 604800 86400

;; Query time: 71 msec
;; SERVER: 195.22.175.1#53(195.22.175.1)
;; WHEN: Mon Jul 21 14:26:12 2008
;; MSG SIZE  rcvd: 108

Issue the original request again - and the RESERVED15 status is returned.

$ dig @195.22.175.1  +norec achema.com a

; <<>> DiG 9.3.4-P1.1 <<>> @195.22.175.1 +norec achema.com a
; (1 server found)
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: RESERVED15, id: 34203
;; flags: qr ra; QUERY: 1, ANSWER: 0, AUTHORITY: 2, ADDITIONAL: 2

;; QUESTION SECTION:
;achema.com.                    IN      A

;; AUTHORITY SECTION:
achema.com.             7184    IN      NS      ns1.omnitel.net.
achema.com.             7184    IN      NS      ns2.omnitel.net.

;; ADDITIONAL SECTION:
ns1.omnitel.net.        86400   IN      A       194.176.32.129
ns2.omnitel.net.        86400   IN      A       195.22.175.1

;; Query time: 72 msec
;; SERVER: 195.22.175.1#53(195.22.175.1)
;; WHEN: Mon Jul 21 14:26:14 2008
;; MSG SIZE  rcvd: 107

That would explain why it occurs for servers that are both lame, and providing 
recursion. lame meaning others will be asking the same question, and 
providing recursion allowing it to change state in between.

I'll stop poking at other peoples DNS servers for a bit.

Is this the bug mentioned in change 1722 in 8.4.7 ?
http://www.isc.org/index.pl?/sw/bind/view/?release=8.4.7

Or something else?