配置DNS服務（shell腳本一鍵安裝）

[root@lw ~]# cat   install_dns.sh 
#!/bin/bash
echo 
echo "DNS配置中，請稍等... ..."


#安裝提供dns服務器的軟件包 bind  bind-chroot
rpm -q  bind bind-chroot  &> /dev/null  ||  yum  -y  install bind bind-chroot &> /dev/null

#編寫主配置文件/etc/named.conf 定義可以管理的區域
rm  -rf  /etc/named.conf 
cat << EOF > /etc/named.conf
options {
   directory  "/var/named/";
};
zone "lmzf.com" {
     type  master;
     file "lmzf.com.zone";
};
EOF

#編寫區域文件 指定指針記錄 設置可以解析的主機名
cat << EOF  > /var/named/lmzf.com.zone
@    IN     SOA      lmzf.com.    root.lmzf.com.(
            2018102700
            28800
            14400
            17200
            86400
)
     IN     NS        dns.lmzf.com.
dns  IN     A         172.16.26.194
www  IN     A         192.168.1.200
EOF

#啓動DNS服務
systemctl  status  named  &> /dev/null  ||  systemctl  start named 

#在配置文件/etc/resolv.conf第一行前面插入nameserver  172.16.26.194
sed  -i  '1inameserver  172.16.26.194'  /etc/resolv.conf  
sleep  3
echo "DNS配置完成！"

#客戶端測試
echo "執行如下命令 host www.lmzf.com 測試"
echo