RHCE-DNS

概念：域名解析

双向解析：(ip-FQDN一对多)

​ 正向解析 将域名解析成ip

​ 反向解析 将ip解析成域名

端口：53 TCP/UDP协议

DNS解析过程(解析顺序，递归查询，迭代查询，权威答案，非权威答案)

DNS常用的解析记录(资源记录类型)： SOA；NS；A ；AAAA；CNAME；MX；PTR

bind 开源程序实现DNS解析，服务名称named

1.在服务端主机安装服务包
# yum install bind -y 
2.更改配置自定义解析域(baidu.com)
# vim /etc/named.conf
options {
	listen-on port 53{192.168.231.132;};
	directory "/var/named";
	allow-query{any;};
};
zone "baidu.com"IN {
	type master;
	file "named.baidu.com";
};
----------------------------------------
#cp /var/named/named.localhost   /var/named/named.baidu.com
#vim /var/named/named.baidu.com

3.重启服务
systemctl restart named

客户端主机
1.nmcil con modify ens160 ipv4.dns 192.168.231.131
2.vim /etc/resolv.conf
nameserver 192.168.231.131
3.ping
	#nslookup  www.baidu.com
	#dig -t A www.baidu.com

1.主dns服务器修改
在主配置文件options模块追加 allow—transfer {192.168.231.132；}；#辅助DNS服务器ip
2.配置从服务器firewalld selinux
	#yum install bind -y
	#vim /etc/named.conf
options{
		listen-on port 53{ 192.168.231.132;};
		directory	"/var/nameed/slaves";
};
zone  "baidu.com"IN {
		typr slave;
		file "named.baidu";
		masters {192.168.231.131;}; #主服务的ip
}；
#systemctl restart named

主服务器资源记录修改

从服务器查看日志判断传输是否成功

#tail /var/log/messages

转发server

#vim /etc/named.conf

options{

​		listen-on port 53{132.231.168.192;}

​		forwarders{131.231.168.192;}

​		forward only;

}

options{
	listen-on port 53{192.168.231.134;};
	directory 	"/var/named";
	allow-query{"any";};
};
	acl "内网"{192.168.20.0/24;};
	acl "外网"{192.168.30.0/24;};
view "外网"{
	math-cilents{"内网"；}；
	zone "openlab.com"IN{
		type master;
		file"named.openlab.com";
		notify yes;
	};
};
view"vmware"{
	match-cilent{"vmware";};
	zone"openlab.com"IN{
		type master;
		file"named.openlab1.com";
	};
};