【Linux】DNS服务-BIND基础配置

时间:2023-03-10 04:20:31
【Linux】DNS服务-BIND基础配置

1、BIND简介

现在使用最为广泛的DNS服务器软件是BIND(Berkeley Internet Name Domain),最早有伯克利大学的一名学生编写,现在最新的版本是9,有ISC(Internet Systems Consortium)编写和维护。

BIND支持先今绝大多数的操作系统(Linux,UNIX,Mac,Windows)

BIND服务的名称称之为named

DNS默认使用UDP、TCP协议,使用端口为53(domain),953(mdc,远程控制使用)

2、BIND安装

[root@20liuzhenchao ~]# yum install -y bind bind-chroot bind-utils
已加载插件:product-id, search-disabled-repos, subscription-manager
This system is not registered with an entitlement server. You can use subscription-manager to register.
base | 3.6 kB 00:00:00
centosplus | 3.4 kB 00:00:00
epel | 4.7 kB 00:00:00
extras libselinux.x86_64 0:2.5-14.1.el7 libselinux-python.x86_64 0:2.5-14.1.el7 libselinux-utils.x86_64 0:2.5-14.1.el7 libsemanage.x86_64 0:2.5-14.el7
libsepol.x86_64 0:2.5-10.el7 policycoreutils.x86_64 0:2.5-29.el7_6.1 完毕!

3、BIND配置

3.1、BIND配置文件保存在两个位置:

  • /etc/named.conf  - BIND服务主配置文件
  • /var/named/    - zone文件(域的dns信息)

如果安装了bind-chroot(其中chroot是 change root 的缩写),BIND会被封装到一个伪根目录内,配置文件的位置变为:

  • /var/named/chroot/etc/named.conf   -BIND服务主配置文件
  • /var/named/chroot/var/named/    - zone文件

chroot是通过相关文件封装在一个伪根目录内,已达到安全防护的目的,一旦程序被攻破,将只能访问伪根目录内的内容,而不是真实的根目录

3.2、BIND安装好之后不会有预制的配置文件,但是在BIND的文档文件夹内(/usr/share/doc/bind-9.9.4),BIND为我们提供了配置文件模板,我们可以直接拷贝过来:

[root@20liuzhenchao ~]# cp -r /usr/share/doc/bind-9.9.4/sample/etc/* /var/named/chroot/etc/
[root@20liuzhenchao ~]# cp -r /usr/share/doc/bind-9.9.4/sample/var/* /var/named/chroot/var/

3.3、配置BIND服务的主配置文件(/var/named/chroot/etc/named.conf),命令:vim /var/named/chroot/etc/named.conf;

内容很多使用简单配置,删除文件中logging以下的全部内容,以及option中的部分内容,得到如下配置

[root@20liuzhenchao ~]# vim /var/named/chroot/etc/named.conf
Sample named.conf BIND DNS server 'named' configuration file
for the Red Hat BIND distribution. See the BIND Administrator's Reference Manual (ARM) for details about the
configuration located in /usr/share/doc/bind-{version}/Bv9ARM.html
*/ options
{
// Put files that named is allowed to write in the data/ directory:
directory "/var/named"; // "Working" directory //listen-on port 53 { any; };
listen-on port 53 { 127.0.0.1; }; //listen-on-v6 port 53 { any; };
listen-on-v6 port 53 { ::1; }; };

3.4、在主配置文件(/var/named/chroot/etc/named.conf )中加入,zone参数

[root@20liuzhenchao ~]# vim /var/named/chroot/etc/named.conf

 See the BIND Administrator's Reference Manual (ARM) for details about the
configuration located in /usr/share/doc/bind-{version}/Bv9ARM.html
*/ options
{
// Put files that named is allowed to write in the data/ directory:
directory "/var/named"; // "Working" directory //listen-on port 53 { any; };
listen-on port 53 { 127.0.0.1; }; //listen-on-v6 port 53 { any; };
listen-on-v6 port 53 { ::1; }; }; zone "example.net" {
type master;
file "example.net.zone";
};

~

3.5、新建example.net.zone文件,example.net的域名解析文件,zone文件放在/var/named/chroot/var/named/下,zone文件可以已/var/named/chroot/var/named/named.localhost为模板。

[root@0liuzhenchao ~]# cp /var/named/chroot/var/named/named.localhost /var/named/chroot/var/named/example.net.zone
[root@0liuzhenchao ~]# ls /var/named/chroot/var/named/
data example.net.zone my.external.zone.db my.internal.zone.db named.ca named.empty named.localhost named.loopback slaves

文件example.net.zone的内容如下:

[root@20liuzhenchao named]# vim example.net.zone
$TTL 1D
@ IN SOA @ rname.invalid. (
0 ; serial
1D ; refresh
1H ; retry
1W ; expire
3H ) ; minimum
NS @
A 127.0.0.1
AAAA ::1
www IN A 192.168.0.168

3.6、禁用bind默认方式启动,改用bind-chroot方式启动。命令如下:

[root@20liuzhenchao named]# /usr/libexec/setup-named-chroot.sh /var/named/chroot on
[root@20liuzhenchao named]# systemctl stop named
[root@20liuzhenchao named]# systemctl disable named
[root@20liuzhenchao named]# systemctl start named-chroot
[root@20liuzhenchao named]# systemctl enable named-chroot
Created symlink from /etc/systemd/system/multi-user.target.wants/named-chroot.service to /usr/lib/systemd/system/named-chroot.service.

3.7、查看是否启动,命令:ps -ef|grep named

[root@0liuzhenchao named]# ps -ef |grep named
named 5904 1 0 06:19 ? 00:00:00 /usr/sbin/named -u named -c /etc/named.conf -t /var/named/chroot
root 6007 1392 0 06:21 pts/0 00:00:00 grep --color=auto named

3.8、测试DNS服务,本例在本机上测试,也可在其他电脑上测试,修改DNS服务的ip地址即可(命令:vim /etc/resolv.conf ),然后使用命令dig(命令:dig www.example.net)测试

[root@20liuzhenchao ~]# vim /etc/resolv.conf
# Generated by NetworkManager
#nameserver 114.114.114.114
nameserver 127.0.0.1 //测试结果:
[root@20liuzhenchao ~]# dig www.example.net ; <<>> DiG 9.9.4-RedHat-9.9.4-73.el7_6 <<>> www.example.net
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 59100
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 3 ;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;www.example.net. IN A ;; ANSWER SECTION:
www.example.net. 86400 IN A 192.168.0.168 //域名解析的IP地址 ;; AUTHORITY SECTION:
example.net. 86400 IN NS example.net. ;; ADDITIONAL SECTION:
example.net. 86400 IN A 127.0.0.1
example.net. 86400 IN AAAA ::1 ;; Query time: 0 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
//DNS服务器地址
;; WHEN: 三 5月 01 06:29:56 CST 2019
;; MSG SIZE rcvd: 118

注:非本机测试需要修改主配置文件named.conf,允许任何ip访问,然后重启服务器