Linux的DNS配置3-多域

1、实验目的

　　现要求在两个局域网中分别搭建各自的DNS服务器，并通过相关设置，使得两个DNS服务器能相互解析

2、实验拓扑

3、实验分析

　　要使两个不同网络的DNS服务器能相互访问，需要额外假设一台DNS服务器，同时作为网关

4、实验步骤

（1）搭建如图所示基础网络

　　使得alice能访问bob（参考Linux基础网络搭建实验）

（2）在alice（192.168.0.253）上

1）安装DNS服务器（参考：配置Yum源）

[root@lyy yum.repos.d]# yum install bind -y

2）配置主配置文件

[root@lyy yum.repos.d]# gedit /etc/named.conf

options {

    listen-on port  { any; };

    directory     "/var/named";

    dump-file     "/var/named/data/cache_dump.db";

      statistics-file "/var/named/data/named_stats.txt";

      memstatistics-file "/var/named/data/named_mem_stats.txt";

    allow-query     { any; };

    forward only;  //即使有根服务器，也不询问，转发给上层DNS服务器

    forwarders {192.168.0.254;}; //转发对象（上层DNS）的地址

};

zone "alice.com"    IN {

    type master;

    file "named.alice.com";

};

zone "0.168.192.in-addr.arpa" IN {

    type master;

    file "named.192.168.0";

};

3）正解文件

[root@lyy yum.repos.d]# cd /var/named/

[root@lyy named]# touch named.alice.com

[root@lyy named]# gedit named.alice.com

$TTL 3H

@    IN SOA    master.alice.com. admin.mail.alice.com. (

                        ; serial

                    1D    ; refresh

                    1H    ; retry

                    1W    ; expire

                    3H )    ; minimum

@                 IN     NS        master.alice.com.

master.alice.com.        IN    A        192.168.0.253

@                IN    MX        mail.alice.com.

mail.alice.com.        IN    A        192.168.0.253

ftp.alice.com.        IN    CNAME        master.alice.com.

www.alice.com.        IN    CNAME        master.alice.com.

client.alice.com.        IN    A        192.168.0.10

nfs.alice.com.        IN    A        192.168.0.11

4）反解文件

[root@lyy named]# touch named.192.168.

[root@lyy named]# gedit named.192.168.

$TTL 3H

@    IN SOA    master.alice.com. admin.mail.alice.com. (

                        ; serial

                    1D    ; refresh

                    1H    ; retry

                    1W    ; expire

                    3H )    ; minimum

@         IN     NS        master.alice.com.

        IN    PTR        master.alice.com.

        IN    PTR        mail.alice.com.

        IN    PTR        client.alice.com.

        IN    PTR        nfs.alice.com.

5）防火墙设置

[root@lyy named]# iptables -I INPUT -i eth0 -p udp --dport  -j ACCEPT

[root@lyy named]# iptables -I INPUT -i eth0 -p tcp --dport  -j ACCEPT

6）启动DNS服务

[root@lyy named]# service named start

（3）在bob（202.3.4.253）上

1）安装DNS服务器

2）主配置文件

options {

    listen-on port  { any; };

    directory     "/var/named";

    dump-file     "/var/named/data/cache_dump.db";

      statistics-file "/var/named/data/named_stats.txt";

      memstatistics-file "/var/named/data/named_mem_stats.txt";

    allow-query     { any; };

    forward only; //即使有根服务器，也不询问，转发给上层DNS服务器

    forwarders {202.3.4.254;}; //转发对象（上层DNS）的地址

};

zone "bob.com"    IN {

    type master;

    file "named.bob.com";

    };

zone "4.3.202.in-addr.arpa" IN {

    type master;

    file "named.202.3.4";

};

3）正解文件（参考alice）

$TTL 3H

@    IN SOA    master.bob.com. admin.mail.bob.com. (

                        ; serial

                    1D    ; refresh

                    1H    ; retry

                    1W    ; expire

                    3H )    ; minimum

@                 IN     NS        master.bob.com.

master.bob.com.        IN    A        202.3.4.253

@                IN    MX        mail.bob.com.

mail.bob.com.        IN    A        202.3.4.253

ftp.bob.com.        IN    CNAME        master.bob.com.

www.bob.com.        IN    CNAME        master.bob.com.

client.bob.com.        IN    A        202.3.4.10

nfs.bob.com.        IN    A        202.3.4.11

4）反解文件

$TTL 3H

@    IN SOA    master.bob.com. admin.mail.bob.com. (

                        ; serial

                    1D    ; refresh

                    1H    ; retry

                    1W    ; expire

                    3H )    ; minimum

@         IN     NS        master.bob.com.

        IN    PTR        master.bob.com.

        IN    PTR        mail.bob.com.

        IN    PTR        client.bob.com.

        IN    PTR        nfs.bob.com.

5）防火墙设置

[root@lyy named]# iptables -I INPUT -i eth0 -p udp --dport  -j ACCEPT

[root@lyy named]# iptables -I INPUT -i eth0 -p tcp --dport  -j ACCEPT

6）启动DNS服务

[root@lyy named]# service named start

（4）在网关（com）上

1）安装DNS服务

2）主配置文件

options {

    listen-on port  { any; };

    directory     "/var/named";

    dump-file     "/var/named/data/cache_dump.db";

      statistics-file "/var/named/data/named_stats.txt";

      memstatistics-file "/var/named/data/named_mem_stats.txt";

    allow-query     { any; };

    allow-transfer {none; };

};

zone "." IN {

    type hint;

    file "named.ca";

};

zone "com"    IN {

    type master;

    file "named.com";

};

3）正解文件

[root@lyy yum.repos.d]# cd /var/named/

[root@lyy named]# touch named.com

[root@lyy named]# gedit named.com

$TTL 3H

@    IN SOA    master.com. admin.mail.com. (

                        ; serial

                    1D    ; refresh

                    1H    ; retry

                    1W    ; expire

                    3H )    ; minimum

@                 IN     NS        master.com.

master.com.            IN    A        192.168.0.254

alice.com.            IN    NS        master.alice.com.

master.alice.com.        IN    A        192.168.0.253

bob.com.            IN    NS        master.bob.com.

master.bob.com.        IN    A        202.3.4.253

注意：（com）不需要反解文件

4）防火墙设置

[root@lyy named]# iptables -I INPUT  -p udp --dport  -j ACCEPT

[root@lyy named]# iptables -I INPUT  -p tcp --dport  -j ACCEPT

5）启动DNS服务

5、结果测试

（1）在alice.com的DNS Server上测试

[root@lyy named]# dig -t mx bob.com

（2）在bob.com的DNS Server上测试

[root@lyy named]# dig -t mx alice.com

可以看到，alice和bob的邮件记录能相互解析，实验成功！

巴特西