DNS反向域名解析之bind
客户端解析不成功
[14:42:08 root@sz-kx-centos8 ~]# dig -t ptr 48.0.31.172.in-addr.arpa
; <<>> DiG 9.11.20-RedHat-9.11.20-5.el8_3.1 <<>> -t ptr 48.0.31.172.in-addr.arpa
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 13979
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
; COOKIE: 14dd778a5f9d54319bc1428f608fa468b7903b67e3fc2b6f (good)
;; QUESTION SECTION:
;48.0.31.172.in-addr.arpa. IN PTR
;; AUTHORITY SECTION:
31.172.IN-ADDR.ARPA. 86400 IN SOA 31.172.IN-ADDR.ARPA. . 0 28800 7200 604800 86400
;; Query time: 1 msec
;; SERVER: 172.31.0.38#53(172.31.0.38)
;; WHEN: Mon May 03 15:21:13 CST 2021
;; MSG SIZE rcvd: 135
DNS服务端改配置文件
[root@localhost named]# vim /etc/named.rfc1912.zones
zone "0.31.172.in-addr.arpa"{
type master;
file "172.31.0.zone";
};
改反向配置文件
[root@localhost named]# vim /var/named/172.31.0.zone
$TTL 1D
@ IN SOA ns1 admin.longxuan.vip.(
2021050100 ; serial
1D ; refresh
1H ; retry
1W ; expire
3H ) ; minimum
NS ns1.longxuan.vip.
48 PTR www.longxuan.vip.
100 PTR app.longge.vip.
改权限并改所属组
[root@localhost named]# chmod 640 172.31.0.zone
[root@localhost named]# chgrp named 172.31.0.zone
重启服务
[root@localhost named]# rndc reload
server reload successful
客户端重新验证
[15:21:13 root@sz-kx-centos8 ~]# dig -t ptr 48.0.31.172.in-addr.arpa
; <<>> DiG 9.11.20-RedHat-9.11.20-5.el8_3.1 <<>> -t ptr 48.0.31.172.in-addr.arpa
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 40791
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 2
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
; COOKIE: 954097d2ed4bdd438b6d65a3608fa4ea5d07d1cf22eb93ec (good)
;; QUESTION SECTION:
;48.0.31.172.in-addr.arpa. IN PTR
;; ANSWER SECTION:
48.0.31.172.in-addr.arpa. 86400 IN PTR www.longxuan.vip.
;; AUTHORITY SECTION:
0.31.172.in-addr.arpa. 86400 IN NS ns1.longxuan.vip.
;; ADDITIONAL SECTION:
ns1.longxuan.vip. 86400 IN A 172.31.0.48
;; Query time: 0 msec
;; SERVER: 172.31.0.38#53(172.31.0.38)
;; WHEN: Mon May 03 15:23:23 CST 2021
;; MSG SIZE rcvd: 145
实验
没有缓存的情况
服务端停止DNS
[root@localhost named]# rndc stop
客户端验证
[15:23:23 root@sz-kx-centos8 ~]# ping www.longxuan.vip
ping: www.longxuan.vip: Name or service not known
启用缓存
# 安装软件
[15:28:14 root@sz-kx-centos8 ~]# yum -y install nscd
# 启动
[15:32:10 root@sz-kx-centos8 ~]# systemctl enable --now nscd
重新验证
DNS服务端启动
[root@localhost named]# systemctl start named
客户端验证
[15:35:13 root@sz-kx-centos8 ~]# ping www.longxuan.vip
PING vip.longxuan.vip (172.31.0.48) 56(84) bytes of data.
64 bytes from www.longxuan.vip (172.31.0.48): icmp_seq=1 ttl=64 time=0.257 ms
64 bytes from www.longxuan.vip (172.31.0.48): icmp_seq=2 ttl=64 time=0.339 ms
64 bytes from www.longxuan.vip (172.31.0.48): icmp_seq=3 ttl=64 time=0.166 ms
DNS服务端停止
[root@localhost named]# rndc stop
客户端再次验证
[15:35:19 root@sz-kx-centos8 ~]# ping www.longxuan.vip
PING vip.longxuan.vip (172.31.0.48) 56(84) bytes of data.
64 bytes from www.longxuan.vip (172.31.0.48): icmp_seq=1 ttl=64 time=0.166 ms
64 bytes from www.longxuan.vip (172.31.0.48): icmp_seq=2 ttl=64 time=0.304 ms
64 bytes from www.longxuan.vip (172.31.0.48): icmp_seq=3 ttl=64 time=0.241 ms
64 bytes from www.longxuan.vip (172.31.0.48): icmp_seq=4 ttl=64 time=0.779 ms
临时清除缓存
[15:43:01 root@sz-kx-centos8 ~]# nscd -i hosts
Ubuntu启动缓存
[root@ubuntu1804 ~]#systemctl status systemd-resolved.service
