UNbound DNS -UNbound域名解析

1. UNbound DNS服务器简介：
   RHEL7.x自带了Bind和Unbound两种DNS服务包,Unbound是红帽公司推荐使用的DNS服务器。目前,虽然Bind在全球拥有最多的用户,但这个老牌产品是针对简单网络设计的,随着网络的迅速发展,Bind系统已经越来越不适应在如今复杂的大规模网络环境下提供DNS服务了。Unbound是FreeBSD(类Unix)操作系统下的默认DNS服务器软件,它是一个功能强大、安全性高、跨平台(类Unix、Linux、Windows)、易于配置,以及支持验证、递归(转发)、缓存等功能的DNS服务软件
2. unbound dns服务器配置：
   （前提是光盘已挂载，yum源已配置，防火墙关闭，selinux为警告模式）

• 检查是否已经安装软件包

[root@llh ~]# rpm -qa unbound*     //检查安装包
unbound-libs-1.4.20-26.el7.x86_64
[root@llh ~]# yum list | grep ^unbound    //
unbound-libs.x86_64                     1.4.20-26.el7              @anaconda/7.2
unbound.x86_64                          1.4.20-26.el7              base    //主安装包    
unbound-libs.i686                       1.4.20-26.el7              base         

• 安装软件包:

[root@llh ~]# yum install unbound -y
[root@llh ~]# rpm -qc unbound      //查看相关配置文件及目录
/etc/sysconfig/unbound          
/etc/unbound/conf.d/example.com.conf
/etc/unbound/keys.d/example.com.key
/etc/unbound/local.d/block-example.com.conf
/etc/unbound/unbound.conf           //主(全局)配置文件

• 配置主配置文件

[root@llh ~]# vim /etc/unbound/unbound.conf 
 38         interface: 192.168.154.140       //设置监听的网络接口(默认监听localhost网络接口)
 176         access-control: 192.168.154.0/24 allow      //允许allow或拒绝refuse给哪些地址提供解析服务
 211         username: ""      //改成空字符串,表示任何用户均可访问
372         domain-insecure: "haha.edu"    //跳过验证域“haha.edu”,以避免信任链验证失败

• 配置区域文件----正向解析记录和反向解析记录

[root@llh ~]# cd /etc/unbound/local.d/    //模板所在目录
[root@llh local.d]# ll
total 4
-rw-rw-r--. 1 root unbound 359 Sep 22  2015 block-example.com.conf  //模板
复制模板进行配置：
[root@llh local.d]# cp -p block-example.com.conf haha.edu.conf    //正反向解析文件名结尾一定为.conf
[root@llh local.d]# vim haha.edu.conf 
 11 # 正向解析
 12 local-data: "haha.edu.  86400           IN  SOA  ns1.haha.edu.  root.haha.edu  1 1D 1H 1W 1H"
 13 local-data: "ns1.haha.edu.              IN  A        192.168.154.140"
 14 local-data: "ns2.haha.edu.              IN  A        192.168.154.11"
 15 local-data: "www.haha.edu.              IN  A        192.168.154.12"
 16 local-data: "web.haha.edu.              IN  CNAME     www.haha.edu."
 17 local-data: "mail.haha.edu.             IN  A        192.168.154.140"
 18 local-data: "haha.edu.                  IN  MX  5   mail.haha.edu."
 19 #反向解析
 20 local-data-ptr: "192.168.154.140   ns1.haha.edu"
 21 local-data-ptr: "192.168.154.11     ns2.haha.edu"
 22 local-data-ptr: "192.168.154.12     www.haha.edu"
 23 local-data-ptr: "192.168.154.12     web.haha.edu"
 24 local-data-ptr: "192.168.154.140     mail.haha.edu"

也可以直接在主配置文件中进行配置，以下给出参考模板：

[root@dns1~]# vim  /etc/unbound/unbound.conf
local-zone: "haha.edu."  static	      //455行:设置解析的区域名
//添加以下7行local-data,以定义正向解析记录
 local-data: "haha.edu.  86400     IN  SOA  ns1.haha.edu.  root.haha.edu  1 1D 1H 1W 1H"
 local-data: "ns1.haha.edu.          IN  A        192.168.154.140"
local-data: "ns2.haha.edu.           IN  A        192.168.154.11"
 local-data: "www.haha.edu.        IN  A        192.168.154.12"
 local-data: "web.haha.edu.         IN  CNAME     www.haha.edu."
 local-data: "mail.haha.edu.         IN  A          192.168.154.140"
 local-data: "haha.edu.                 IN  MX  5   mail.haha.edu."
//添加以下5行local-data-ptr,以定义反向解析记录
local-data-ptr: "192.168.154.140   ns1.haha.edu"
local-data-ptr: "192.168.154.11     ns2.haha.edu"
local-data-ptr: "192.168.154.12     www.haha.edu"
local-data-ptr: "192.168.154.12     web.haha.edu"
local-data-ptr: "192.168.154.140     mail.haha.edu"

• 语法测试并重启：

[root@llh local.d]# unbound-checkconf
/etc/unbound/unbound_server.key: No such file or directory
[1584074279] unbound-checkconf[5445:0] fatal error: server-key-file: "/etc/unbound/unbound_server.key" does not exist     //发现报错，显示该文件不存在
报错处理： 对报错中的文件进行注释：
[root@llh ~]# vim /etc/unbound/unbound.conf 
499         #control-enable: yes
510         #server-key-file: "/etc/unbound/unbound_server.key"
513         #server-cert-file: "/etc/unbound/unbound_server.pem"
516         #control-key-file: "/etc/unbound/unbound_control.key"
519         #control-cert-file: "/etc/unbound/unbound_control.pem"
再次测试：
[root@llh local.d]# unbound-checkconf
unbound-checkconf: no errors in /etc/unbound/unbound.conf   //显示配置文件没有错误即配置成功
重启：
[root@llh local.d]# systemctl start unbound   //启用无报错

• 测试：

[root@llh local.d]# nslookup
> server 192.168.154.140     //指定dns服务地址
Default server: 192.168.154.140
Address: 192.168.154.140#53
> www.haha.edu
Server:		192.168.154.140
Address:	192.168.154.140#53
Name:	www.haha.edu
> set type=cname   //别名测试
> web.haha.edu
Server:		192.168.154.140
Address:	192.168.154.140#53
web.haha.edu	canonical name = www.haha.edu.
> set type=mx    //邮件测试需指定type
> haha.edu
Server:		192.168.154.140
Address:	192.168.154.140#53
haha.edu	mail exchanger = 5 mail.haha.edu.
> 192.168.154.12            //反向测试
Server:		192.168.154.140
Address:	192.168.154.140#53
12.154.168.192.in-addr.arpa	name = www.haha.edu.
12.154.168.192.in-addr.arpa	name = web.haha.edu.
> 192.168.154.140     //反向测试
Server:		192.168.154.140
Address:	192.168.154.140#53
140.154.168.192.in-addr.arpa	name = ns1.haha.edu.
140.154.168.192.in-addr.arpa	name = mail.haha.edu.
> exit  //退出
或者用host测试：
[root@llh local.d]# host -t mx haha.edu 192.168.154.140
Using domain server:
Name: 192.168.154.140
Address: 192.168.154.140#53
Aliases: 
haha.edu mail is handled by 5 mail.haha.edu.

也可以像bind dns一样配置永久测试文件：
[root@client ~]# vim /etc/resolv.conf
nameserver 192.168.154.140