리눅스 dns서버 구축 질문이요

리눅스는 CentOS 5.X 쓰고요
현재 DB서버를 111 웹서버를 112, 113 쓰고 있습니다
DB서버(111)에다가 DNS서버를 구축하려 하는데요
이틀동안 내내 알아보고 했는데 잘안되는거 같습니다
설정이 잘 되어있는지좀 봐주세요..ㅠㅠ
호스트네임은 보안상 aaa.or.kr로 할게요
111을 DNS서버로
112를 aaa.or.kr
113은 bbb.aaa.or.kr로 하려고 하였습니다

/etc/sysconfig/network
----------------------
networking=yes
networking_ipv6=no
hostname=aaa.or.kr

/etc/hosts
-----------------------------------------------
127.0.0.1 localhost.localdomain localhost
::1 localhost6.localdomain6 localhost6
123.456.789.111 aaa.or.kr

/etc/resolv.conf
--------------------------
nameserver 123.456.789.111

/etc/named.conf
-----------------------------------------------
//
// named.conf for Red Hat caching-nameserver
//

options {
 directory "/var/named";
};

zone "." IN {
 type hint;
 file "named.ca";
};

zone "localhost" IN {
 type master;
 file "localhost.zone";
 allow-update { none; };
};

zone "0.0.127.in-addr.arpa" IN {
 type master;
 file "named.local";
 allow-update { none; };
};

zone "aaa.or.kr" IN {
 type master;
 file "named.aaa.or.kr";
};

zone "789.456.123.in-addr.arpa" IN {
 type master;
 file "named.rev";
};

/var/named/localhost.zone
----------------------------------------------
$TTL 86400
@  IN SOA ns.aaa.or.kr. mail.aaa.or.kr. (
    2009902101 ; serial (d. adams)
    3H  ; refresh
    15M  ; retry
    1W  ; expiry
    1D )  ; minimum

  IN NS  @
  IN A  127.0.0.1
  IN AAAA  ::1
112  IN PTR  aaa.or.kr.
112  IN PTR  www.aaa.or.kr.
113  IN PTR  bbb.aaa.or.kr.

/var/named/named.local
----------------------------------------------
$TTL 86400
@ IN SOA localhost. root.localhost. (
     2009102700 ; serial
     28880  ; refresh
     14400  ; retry
     3600000  ; expire
     86400 )  ; minimum
 IN NS localhost.

111 IN PTR localhost.

/var/named/named.aaa.or.kr
-----------------------------------------------
$TTL 86400
@ IN SOA aaa.or.kr. mail.aaa.or.kr. (
     2009102700 ; serial
     28880  ; refresh
     14400  ; retry
     3600000  ; expire
     86400 )  ; minimum
 IN NS ns.aaa.or.kr.
 IN MX 10 mail.aaa.or.kr.
ns IN A 123.456.789.111
www IN A 123.456.789.112
bbb IN A 123.456.789.113

named.rev
----------------------------------------------------------------
$TTL 86400
@ IN SOA 789.456.123.in-addr.arpa. mail.aaa.or.kr.(
     2009102700 ; serial
     28880  ; refresh
     14400  ; retry
     3600000  ; expire
     86400 )  ; minimum
 IN NS ns.aaa.or.kr.
111 IN PTR ns.aaa.or.kr.
112 IN PTR www.aaa.or.kr.
113 IN PTR bbb.aaa.or.kr.