cname quick question

[Brad Knowles]

At 3:17 PM +0000 3/8/01, Jim Reid wrote:

>  I didn't tell you where the the DNAME'd example.com zone was. :-) It's
>  on my laptop which lives at 62.6.242.10 today. It'd be interesting to
>  see what happens when your BIND8 server queries the BIND9 server on my
>  laptop.

	Done:

$ dig @62.6.242.10 example.com. any

; <<>> DiG 8.3 <<>> @62.6.242.10 example.com. any
; (1 server found)
;; res options: init recurs defnam dnsrch
;; got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 6
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 6, AUTHORITY: 3, ADDITIONAL: 3
;; QUERY SECTION:
;;      example.com, type = ANY, class = IN

;; ANSWER SECTION:
example.com.            1D IN SOA       gromit.rfc1035.com. 
hostmaster.rfc1035.com. (
                                         2001030400      ; serial
                                         3H              ; refresh
                                         1H              ; retry
                                         4w2d            ; expiry
                                         1D )            ; minimum

example.com.            1D IN 39        \#(             ; unknown RR type
         07 72 66 63 31 30 33 35 03 63 6f 6d 00 )        ; .rfc1035.com.
example.com.            1D IN TXT       "$Id: example.com,v 1.1 
2000/10/30 21:31:20 jim Exp $"
example.com.            1D IN NS        ns0.rfc1035.com.
example.com.            1D IN NS        ns1.rfc1035.com.
example.com.            1D IN NS        ns2.rfc1035.com.

;; AUTHORITY SECTION:
example.com.            1D IN NS        ns0.rfc1035.com.
example.com.            1D IN NS        ns1.rfc1035.com.
example.com.            1D IN NS        ns2.rfc1035.com.

;; ADDITIONAL SECTION:
ns0.rfc1035.com.        1D IN A         62.6.242.6
ns1.rfc1035.com.        1D IN A         198.133.199.1
ns2.rfc1035.com.        1D IN A         198.133.199.2

;; Total query time: 180 msec
;; WHEN: Thu Mar  8 12:19:35 2001
;; MSG SIZE  sent: 29  rcvd: 325

$ dig @62.6.242.10 example.com. dname

; <<>> DiG 8.3 <<>> @62.6.242.10 example.com. dname
; (1 server found)
;; res options: init recurs defnam dnsrch
;; got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 6
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0
;; QUERY SECTION:
;;      dname, type = A, class = IN

;; AUTHORITY SECTION:
.                       3H IN SOA       A.ROOT-SERVERS.NET. 
hostmaster.nsiregistry.NET. (
                                         2001030800      ; serial
                                         30M             ; refresh
                                         15M             ; retry
                                         1W              ; expiry
                                         1D )            ; minimum


;; Total query time: 3038 msec
;; WHEN: Thu Mar  8 12:19:45 2001
;; MSG SIZE  sent: 23  rcvd: 99

$ dig @62.6.242.10 gromit.example.com. any

; <<>> DiG 8.3 <<>> @62.6.242.10 gromit.example.com. any
; (1 server found)
;; res options: init recurs defnam dnsrch
;; got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 6
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 5, AUTHORITY: 5, ADDITIONAL: 3
;; QUERY SECTION:
;;      gromit.example.com, type = ANY, class = IN

;; ANSWER SECTION:
example.com.            1D IN 39        \#(             ; unknown RR type
         07 72 66 63 31 30 33 35 03 63 6f 6d 00 )        ; .rfc1035.com.
gromit.example.com.     1D IN CNAME     gromit.rfc1035.com.
gromit.rfc1035.com.     1D IN A         62.6.242.6
gromit.rfc1035.com.     1D IN A         62.6.242.9
gromit.rfc1035.com.     1D IN MX        10 gromit.rfc1035.com.

;; AUTHORITY SECTION:
rfc1035.com.            1D IN NS        ns1.bt.net.
rfc1035.com.            1D IN NS        ns1.rfc1035.com.
rfc1035.com.            1D IN NS        ns2.rfc1035.com.
rfc1035.com.            1D IN NS        ns-ext.vix.com.
rfc1035.com.            1D IN NS        ns0.rfc1035.com.

;; ADDITIONAL SECTION:
ns0.rfc1035.com.        1D IN A         62.6.242.6
ns1.rfc1035.com.        1D IN A         198.133.199.1
ns2.rfc1035.com.        1D IN A         198.133.199.2

;; Total query time: 156 msec
;; WHEN: Thu Mar  8 12:22:11 2001
;; MSG SIZE  sent: 36  rcvd: 281


	Well, at least the program didn't crash.  ;-)

	Now, if there were some other zones you had with DNAME 
information in them, and which were available through the delegation 
chain starting at the TLD nameservers, I could compare what dig shows 
me when I contact your servers directly against what I see through my 
own local caching nameservers for those same objects.  I could also 
see if "doc" blows up when trying to do queries of this sort.

--
Brad Knowles, <brad.knowles at skynet.be>

#!/usr/bin/perl -w
# 531-byte qrpff-fast, Keith Winstein and Marc Horowitz <sipb-iap-dvd at mit.edu>
# MPEG 2 PS VOB file on stdin -> descrambled output on stdout
# arguments: title key bytes in least to most-significant order
# Usage:
# qrpff 153 2 8 105 225 /mnt/dvd/VOB_FILE_NAME | extract_mpeg2 | mpeg2_dec -
$_='while(read+STDIN,$_,2048){$a=29;$b=73;$c=142;$t=255;@t=map{$_%16or$t^=$c^=(
$m=(11,10,116,100,11,122,20,100)[$_/16%8])&110;$t^=(72, at z=(64,72,$a^=12*($_%16
-2?0:$m&17)),$b^=$_%64?12:0, at z)[$_%8]}(16..271);if((@a=unx"C*",$_)[20]&48){$h
=5;$_=unxb24,join"", at b=map{xB8,unxb8,chr($_^$a[--$h+84])}@ARGV;s/...$/1$&/;$
d=unxV,xb25,$_;$e=256|(ord$b[4])<<9|ord$b[3];$d=$d>>8^($f=$t&($d>>12^$d>>4^
$d^$d/8))<<17,$e=$e>>8^($t&($g=($q=$e>>14&7^$e)^$q*8^$q<<6))<<9,$_=$t[$_]^
(($h>>=8)+=$f+(~$g&$t))for at a[128..$#a]}print+x"C*", at a}';s/x/pack+/g;eval