[CentOS] resolving names it is really slow slow with CentOS5.x using named

Mon May 25 11:35:49 UTC 2009
Lars Hecking <lhecking at users.sourceforge.net>

> options {
>          directory "/var/named";
>          dump-file "/var/named/data/cache_dump.db";
>          statistics-file "/var/named/data/named_stats.txt";
>          memstatistics-file "/var/named/data/named_mem_stats.txt";
>          listen-on port 53 { 127.0.0.1; 172.25.50.10; };
>          version "DNS Server v2.0";
>          dnssec-enable no;
>          query-source port 53;
>          forwarders { 208.67.220.220; 208.67.222.222; };
> };
 
> As you can see, I need to use "query-source port" param too with forwarders to
> resolv names (and this is really really ugly).
 
 Explicit query-source port breaks port randomisation and is highly insecure.
 Your problem may be an incorrectly configured firewall that only accepts
 outgoing queries originating from source port 53 - it needs to accept all
 outgoing queries for destination port 53.