[Pdns-users] DNS answer don't fit UDP packet
Antoine Levavasseur
pdns at vava.org
Fri Oct 10 15:05:52 UTC 2003
Hi,
I got some problems with powerdns answers which don't fit in UDP packet
;; Warning: Message parser reports malformed message packet.
;; Truncated, retrying in TCP mode.
; <<>> DiG 9.2.1 <<>> -t MX @213.228.0.82 free.fr
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 39773
;; flags: qr aa rd; QUERY: 1, ANSWER: 11, AUTHORITY: 0, ADDITIONAL: 19
;; QUESTION SECTION:
;free.fr. IN MX
;; ANSWER SECTION:
free.fr. 86400 IN MX 10 mx.free.fr.
free.fr. 86400 IN MX 20 mrelay4-1.free.fr.
free.fr. 86400 IN MX 20 mrelay4-2.free.fr.
free.fr. 86400 IN MX 20 mrelay5-1.free.fr.
free.fr. 86400 IN MX 20 mrelay5-2.free.fr.
free.fr. 86400 IN MX 30 mrelay1-2.free.fr.
free.fr. 86400 IN MX 30 mrelay2-1.free.fr.
free.fr. 86400 IN MX 30 mrelay2-2.free.fr.
free.fr. 86400 IN MX 30 mrelay3-1.free.fr.
free.fr. 86400 IN MX 30 mrelay3-2.free.fr.
free.fr. 86400 IN MX 40 mx1-1.free.fr.
;; ADDITIONAL SECTION:
mx.free.fr. 86400 IN A 213.228.0.129
mx.free.fr. 86400 IN A 213.228.0.13
mx.free.fr. 86400 IN A 213.228.0.131
mx.free.fr. 86400 IN A 213.228.0.49
mx.free.fr. 86400 IN A 213.228.0.166
mx.free.fr. 86400 IN A 213.228.0.63
mx.free.fr. 86400 IN A 213.228.0.175
mx.free.fr. 86400 IN A 213.228.0.78
mx.free.fr. 86400 IN A 213.228.0.199
mrelay4-1.free.fr. 86400 IN A 213.228.0.63
mrelay4-2.free.fr. 86400 IN A 213.228.0.175
mrelay5-1.free.fr. 86400 IN A 213.228.0.78
mrelay5-2.free.fr. 86400 IN A 213.228.0.199
mrelay1-2.free.fr. 86400 IN A 213.228.0.129
mrelay2-1.free.fr. 86400 IN A 213.228.0.13
mrelay2-2.free.fr. 86400 IN A 213.228.0.131
mrelay3-1.free.fr. 86400 IN A 213.228.0.49
mrelay3-2.free.fr. 86400 IN A 213.228.0.166
mx1-1.free.fr. 86400 IN A 213.228.0.65
;; Query time: 10 msec
;; SERVER: 213.228.0.82#53(213.228.0.82)
;; WHEN: Fri Oct 10 15:33:36 2003
;; MSG SIZE rcvd: 604
The anwser contains every A entry of my MX and the MSG SIZE 604
is too big for UDP resulting in many errors for mail delivery.
BIND when receiving an UDP query shrink ADDITIONAL SECTION in order
to fit into UDP
because of the round robin ADDITIONAL SECTION vary on every answer.
; <<>> DiG 9.2.3rc4 <<>> -t MX @ns0.proxad.net free.fr
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 57926
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 11, AUTHORITY: 2, ADDITIONAL:
10
;; QUESTION SECTION:
;free.fr. IN MX
;; ANSWER SECTION:
free.fr. 86400 IN MX 30 mrelay1-2.free.fr.
free.fr. 86400 IN MX 30 mrelay2-1.free.fr.
free.fr. 86400 IN MX 30 mrelay2-2.free.fr.
free.fr. 86400 IN MX 30 mrelay3-1.free.fr.
free.fr. 86400 IN MX 30 mrelay3-2.free.fr.
free.fr. 86400 IN MX 40 mx1-1.free.fr.
free.fr. 86400 IN MX 10 mx.free.fr.
free.fr. 86400 IN MX 20 mrelay4-1.free.fr.
free.fr. 86400 IN MX 20 mrelay4-2.free.fr.
free.fr. 86400 IN MX 20 mrelay5-1.free.fr.
free.fr. 86400 IN MX 20 mrelay5-2.free.fr.
;; AUTHORITY SECTION:
free.fr. 86400 IN NS ns0.proxad.net.
free.fr. 86400 IN NS ns1.proxad.net.
;; ADDITIONAL SECTION:
mrelay1-2.free.fr. 86400 IN A 213.228.0.129
mrelay2-1.free.fr. 86400 IN A 213.228.0.13
mrelay2-2.free.fr. 86400 IN A 213.228.0.131
mrelay3-1.free.fr. 86400 IN A 213.228.0.49
mrelay3-2.free.fr. 86400 IN A 213.228.0.166
mx1-1.free.fr. 86400 IN A 213.228.0.65
mrelay4-1.free.fr. 86400 IN A 213.228.0.63
mrelay4-2.free.fr. 86400 IN A 213.228.0.175
mrelay5-1.free.fr. 86400 IN A 213.228.0.78
mrelay5-2.free.fr. 86400 IN A 213.228.0.199
;; Query time: 12 msec
;; SERVER: 212.27.32.2#53(ns0.proxad.net)
;; WHEN: Fri Oct 10 16:55:18 2003
;; MSG SIZE rcvd: 506
For now I reduced my mx list to fit UDP.
But is there any configuration that makes PDNS shrink ADDITIONAL SECTION
in order to fit UDP and answer UDP query with UDP.
Thanks.
--
Antoine.
More information about the Pdns-users
mailing list