kubernetes实践：内部dns域名解析服务器

操作系统：Ubuntu 16.04

服务器IP：172.18.1.12

1. 安装bind9

apt install bind9 -y

2. 配置解析文件

进入/etc/bind目录下，打开named.conf.local

//
// Do any local configuration here
//

// Consider adding the 1918 zones here, if they are not used in your
// organization
//include "/etc/bind/zones.rfc1918";
// 添加一下内容
// mytest.io 需要解析的根域名
// file     需要配置解析文件的名称
zone "mytest.io" {
        type master;
file "db.mytest.io";
};

3. 配置域解析文件

cp /etc/bind/db.local /var/cache/bind/db.mytest.io

4. 配置域解析文件

cd /var/cache/bind/

cat db.mytest.io 
; BIND data file for local loopback interface
$TTL    604800
@       IN      SOA      dns.mytest.io. root.mytest.io. (
                              2         ; Serial
                         604800         ; Refresh
                          86400         ; Retry
                        2419200         ; Expire
                         604800 )       ; Negative Cache TTL
@       IN      NS      dns.mytest.io.
dns     IN      A       172.18.1.12
rancher IN      A       172.18.1.12
rancher IN      A       172.18.1.13

5. 设置外网转发

打开/etc/bind/name.conf.options中添加上forwarders，可以实现外网转发

forwarders {
     8.8.8.8;
};

6. 启动bind服务器

systemctl start bind9
systemctl enable bind9

7. 配置dns解析

打开/etc/resolvconf/resolv.conf.d/head文件将dns的IP地址写入，写入head的原因是如果在一些公有云环境下/etc/resolv.conf里面的内容会在机器重启后被覆盖，但是写入head就可以默认写入resolv.conf，并且默认在第一行，优先被解析。

cat /etc/resolvconf/resolv.conf.d/head 
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
#     DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN
nameserver 172.18.1.12

8. 测试dns

nslookup rancher.mytest.io

Server:         172.18.1.12
Address:        172.18.1.12#53

Name:   rancher.mytest.io
Address: 172.18.1.13
Name:   rancher.mytest.io
Address: 172.18.1.12