正如badwrs2000兄弟所说的，我们是个提供ISP服务的提供商，前段时间我也给邮件服务器的哪个IP，做了个反向解析，很成功。具体操作情况如下
1）named.conf(假设域名是***com、 邮件服务器的ip是111.222.333.7)
........................
zone "localhost" IN {
type master;
file "localhost.zone";
allow-update { none; };
};
zone "333.222.111.in-addr.arpa" IN {
type master;
file "/var/named/111.222.333.rev";
allow-update { none; };
};
zone "***.com" {
type master;
file "/var/named/***.com.zone";
};
.................................
2） 正向：***.com.zone
$ORIGIN ***.com.
$TTL 43200
@ IN SOA ns1.***.com. root.ns1.***.com. (
1030231155 ; serial
3H ;refresh after 3 hours
3600 ;retry after 1 hour
604800 ;expire after 1 week
86400 ) ;minimum TTL of 1 day
;
; Nameservers
; Put your nameservers here!
IN NS ns1.***.com.
@ IN NS ns2.***.com.
;
; Domain Mail Handlers
;
IN MX 0 mail
;
;
; hosts in order
;
......................................
mail IN A 111.222.333.7
..................................
2）反向：111.222.333.rev
$TTL 43200
@ IN SOA ns1.***.com. root.ns1.***.com. (
1030231154 ; serial
3H ;refresh after 3 hours
3600 ;retry after 1 hour
604800 ;expire after 1 week
86400 ) ;minimum TTL of 1 day
IN NS ns1.***.com.
IN NS ns2.***.com.
7 IN PTR mail.***.com.
3）这个IP反向解析，不仅是域名服务器上得做，还要向上级IP提供商（比如CNNIC）申请，上级将IP做了相应的解析，下面才起作用。总之，得两者都做，才能实现。
