前期准备：反向解析的tree结构是从根往下数，第二级为arpa，第三级为in-addr，第四级为IP，表示出来是：254.58.168.192.in-addr.apra.

1、建立反向解析区域：[root@centos7 ~]# vim /etc/named.rfc1912.zones type master;      file "magedu.com.zones";};zone "localhost.localdomain" IN {        type master;        file "named.localhost";        allow-update { none; };};zone "localhost" IN {        type master;        file "named.localhost";        allow-update { none; };};zone "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa" IN {        type master;        file "named.loopback";        allow-update { none; };};zone "58.168.192.in-addr.arpa" IN {       type master;       file  "named.loopback";       allow-update { none; };};                                                                                                                    "/etc/named.rfc1912.zones" 49L, 1126C照猫画虎，我们添加了zone "58.168.192.in-addr.arpa" IN {       type master;       file  "named.loopback";       allow-update { none; };};        内容！2、[root@centos7 ~]# cd /var/named[root@centos7 named]# lsdata  dynamic  magedu.com.zone  named.ca  named.empty  named.localhost  named.loopback  slaves[root@centos7 named]# vim 192.168.58.zone$TTL  86400@   IN   SOA  master  admin.magedu.com.  (  0  1H  20M  1D  1H )    NS   mastermaster   A  192.168.58.254254      PTR    master.magedu.com.8        PTR   www.magedu.com.9        PTR   www.wange.com.     [root@centos7 named]# rndc reloadserver reload successful       (此处使脚本生效)以上内容为反向解析脚本内容！3、测试反向解析结果如下：

[root@Centos6 ~]# dig -x 192.168.58.254

; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.68.rc1.el6 <<>> -x 192.168.58.254

;; global options: +cmd;; Got answer:;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 7237;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:

;254.58.168.192.in-addr.arpa. IN PTR

;; AUTHORITY SECTION:

58.168.192.in-addr.arpa. 10800 IN SOA 58.168.192.in-addr.arpa. rname.invalid. 0 86400 3600 604800 10800

;; Query time: 7 msec

;; SERVER: 192.168.58.254#53(192.168.58.254);; WHEN: Thu Jan 31 21:06:38 2019;; MSG SIZE rcvd: 94

[root@Centos6 ~]# dig -x 192.168.58.8

; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.68.rc1.el6 <<>> -x 192.168.58.8

;; global options: +cmd;; Got answer:;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 53711;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:

;8.58.168.192.in-addr.arpa. IN PTR

;; AUTHORITY SECTION:

58.168.192.in-addr.arpa. 10800 IN SOA 58.168.192.in-addr.arpa. rname.invalid. 0 86400 3600 604800 10800

;; Query time: 6 msec

;; SERVER: 192.168.58.254#53(192.168.58.254);; WHEN: Thu Jan 31 21:06:49 2019;; MSG SIZE rcvd: 92

[root@Centos6 ~]# dig -x 192.168.58.9

; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.68.rc1.el6 <<>> -x 192.168.58.9

;; global options: +cmd;; Got answer:;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 26461;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:

;9.58.168.192.in-addr.arpa. IN PTR

;; AUTHORITY SECTION:

58.168.192.in-addr.arpa. 10800 IN SOA 58.168.192.in-addr.arpa. rname.invalid. 0 86400 3600 604800 10800

;; Query time: 1 msec

;; SERVER: 192.168.58.254#53(192.168.58.254);; WHEN: Thu Jan 31 21:06:53 2019;; MSG SIZE rcvd: 92

以上内容为反向解析的内容！！！当我们不小心把网址输错了，但是百度，京东，淘宝等网站却还可以访问是为什么？答：他们在下面添加了  *   无论用户输入什么信息，只要后缀正确，均可以访问。[root@centos7 named]# vim  magedu.com.zone$TTL  1D@     IN SOA  master  admin.magedu.com.  (                    20190131             ; serial                    1D     ; refresh                    1H     ; retry                    1W     ; expire                    3H   )  ;  minimun        NS      master    @           A           192.68.58.130master      A           192.168.58.254 www         CNAME       websrv websrv      A           192.168.58.133 blog        A           192.168.58.136 @           mx          10  mailsrv1 @           mx          20  mailsrv2 mailsrv1    A           192.168.58.137 mailsrv2    A           192.168.58.138*            A           192.168.58.254  [root@Centos6 ~]# ping wwwwwwww.magedu.comPING www.magedu.com (101.200.188.230) 56(84) bytes of data.64 bytes from 101.200.188.230: icmp_seq=1 ttl=53 time=5.48 ms64 bytes from 101.200.188.230: icmp_seq=2 ttl=53 time=6.39 ms64 bytes from 101.200.188.230: icmp_seq=3 ttl=53 time=6.84 ms64 bytes from 101.200.188.230: icmp_seq=4 ttl=53 time=5.84 m这是加 *  的效果，[root@Centos6 ~]# ping magedu.comPING magedu.com (101.200.188.230) 56(84) bytes of data.64 bytes from 101.200.188.230: icmp_seq=1 ttl=53 time=7.01 ms64 bytes from 101.200.188.230: icmp_seq=2 ttl=53 time=5.59 ms64 bytes from 101.200.188.230: icmp_seq=3 ttl=53 time=7.43 ms这是加 @ 的效果。