centos7 DNS配置

服务端安装包

yum install bind

DNS 主要配置文件为：

1） /etc/named.conf # 主配置文件
2)  /etc/named.rfc1912.zones # 域名配置文件
3） /var/named/ # zone 配置文件目录

修改 /etc/named.conf 文件

listen-on // 监听 IPV4 地址
listen-on-v6 // 监听 IPV6 地址
allow-query // 设置可以访问 dns 服务器的客户端
修改以下3处:

 listen-on port 53 { any; };
 allow-query     { any; };
  bindkeys-file "/etc/named.iscdlv.key";

修改完的文件如下：

  options {
	listen-on port 53 { any; };
	listen-on-v6 port 53 { ::1; };
	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";
	recursing-file  "/var/named/data/named.recursing";
	secroots-file   "/var/named/data/named.secroots";
	allow-query     { any; };
	
	recursion yes;
	dnssec-enable yes;
	dnssec-validation yes;
	bindkeys-file "/etc/named.iscdlv.key";
	managed-keys-directory "/var/named/dynamic";  
	pid-file "/run/named/named.pid";
	session-keyfile "/run/named/session.key";
};
logging {
        channel default_debug {
                file "data/named.run";
                severity dynamic;
        };
};
zone "." IN {
	type hint;
	file "named.ca";
};
include "/etc/named.rfc1912.zones";
include "/etc/named.root.key";

修改 /etc/named.rfc1912.zones 文件

zone "nexus.com" IN {   <<<<-----正向解析
 
     type master;

     file "nexus.com.zone";
     allow-update { none; };
};

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 "2.98.10.in-addr.arpa" IN {    <<<<-----反向解析所以IP必须写反的.我的IP是10.98.2.60
	type master;
	file "10.98.2.zone";
	allow-update { none; };
};

zone "0.in-addr.arpa" IN {
	type master;
	file "named.empty";
	allow-update { none; };
};

注意文件名要跟域名配置文件中设置的 file 一致

cp  /var/named/named.localhost /var/named/nexus.com.zone

编辑 nexus.com.zone 正向解析配置：

$TTL 1D

@ IN SOA @ nexus.com. (

          0 ; serial

          1D ; refresh

          1H ; retry

          1W ; expire

         3H ) ; minimum
@   NS jb  <<<----域名前缀
jb A 10.98.2.60    <<----域名前缀和本机IP

编辑反向解析配置

cp /var/named/named.localhost /var/named/10.98.2.zone

$TTL 1D
@	IN SOA	@ nexus.com. (
					0	; serial
					1D	; refresh
					1H	; retry
					1W	; expire
					3H )	; minimum
	NS      @	
	AAAA    ::1	
60     PTR      jb.nexus.com.  (注意60是你的IP最后4位数如 1098.2.60就是写上60)

语法检查oK 重启生效

[[e-mail] etc]# named-checkconf
[[e-mail] etc]# named-checkzone nexus.com /var/named/nexus.com.zone 
zone nexus.com/IN: loaded serial 0
OK
[[e-mail] etc]# named-checkzone nexus.com /var/named/10.98.2.zone 
zone nexus.com/IN: loaded serial 0
OK
[[e-mail] etc]# systemctl restart named.service 

防火墙规则

firewall-cmd --permanent --add-service=dns 
firewall-cmd --reload
或者直接放行UDP 53端

设置 linux 客户端安装nslookup命令

yum   install  bind-utils  -y

linux 客户端来做测试。修改 /etc/resovled.conf 文件，添加 DNS 服务器 IP：

nameserver 10.98.2.60

或修改 /etc/sysconfig/network-scripts/ifcfg-XXXXXX 网卡文件，添加 DNS 信息，并将自定义 DNS 服务器设置为 DNS1，然后重启网络：

DNS1=10.98.2.60  # 自定义 DNS 服务器 IP
DNS2=114.114.114.114 # 公共 DNS 服务器 IP

systemctl restart network # 重启网络

重启成功后，查看 /etc/resolved.conf 文件发现自定义 DNS 更改成功。

开始正向解析测试
nslookup jb.nexus.com

Server:		10.98.2.60
Address:	10.98.2.60#53

Name:	jb.nexus.com
Address: 10.98.2.60

dig jb.nexus.com

; <<>> DiG 9.11.4-P2-RedHat-9.11.4-16.P2.el7_8.6 <<>> jb.nexus.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 21231
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;jb.nexus.com.			IN	A

;; ANSWER SECTION:
jb.nexus.com.		86400	IN	A	10.98.2.60

;; AUTHORITY SECTION:
nexus.com.		86400	IN	NS	jb.nexus.com.

;; Query time: 0 msec
;; SERVER: 10.98.2.60#53(10.98.2.60)

ping jb.nexus.com

PING jb.nexus.com (10.98.2.60) 56(84) bytes of data.
64 bytes from jb.nexus.com (10.98.2.60): icmp_seq=1 ttl=64 time=0.120 ms
64 bytes from jb.nexus.com (10.98.2.60): icmp_seq=2 ttl=64 time=0.250 ms
64 bytes from jb.nexus.com (10.98.2.60): icmp_seq=3 ttl=64 time=0.313 ms
;; WHEN: 四 7月 23 15:22:40 CST 2020
;; MSG SIZE  rcvd: 71

反向解析

[[e-mail] ~]# nslookup 10.98.2.60
60.2.98.10.in-addr.arpa	name = jb.nexus.com.