DNS解析相关实验：7台主机的恩怨情仇

冷不防 2022-01-11 14:49 208阅读 0赞

# 关于DNS解析 #

## 7台主机的故事 ##

### 7台主机纠缠不休的往事 ###

#### 这是一个男默女泪的催人泪下的真实故事 ####

##### 情节离奇曲折，事件接二连三，到底是怎样的执着让众多运维工程师掩面而泣 #####

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2019.4.23

Tuvia_24

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<table> 
 <thead> 
  <tr> 
   <th style="text-align:center;">序号</th> 
   <th>实现功能</th> 
   <th style="text-align:center;">实现功能</th> 
   <th style="text-align:left;">IP</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td style="text-align:center;">1</td> 
   <td>Clint</td> 
   <td style="text-align:center;">客户端</td> 
   <td style="text-align:left;">192.168.36.6</td> 
  </tr> 
  <tr> 
   <td style="text-align:center;">2</td> 
   <td>LDNS</td> 
   <td style="text-align:center;">本地DNS</td> 
   <td style="text-align:left;">192.168.36.7</td> 
  </tr> 
  <tr> 
   <td style="text-align:center;">3</td> 
   <td>RootDNS</td> 
   <td style="text-align:center;">根域</td> 
   <td style="text-align:left;">192.168.36.17</td> 
  </tr> 
  <tr> 
   <td style="text-align:center;">4</td> 
   <td>com</td> 
   <td style="text-align:center;">com</td> 
   <td style="text-align:left;">192.168.36.27</td> 
  </tr> 
  <tr> 
   <td style="text-align:center;">5</td> 
   <td>Master</td> 
   <td style="text-align:center;">主服务器</td> 
   <td style="text-align:left;">192.168.36.37</td> 
  </tr> 
  <tr> 
   <td style="text-align:center;">6</td> 
   <td>Slaves</td> 
   <td style="text-align:center;">从服务器</td> 
   <td style="text-align:left;">192.168.36.47</td> 
  </tr> 
  <tr> 
   <td style="text-align:center;">7</td> 
   <td>www</td> 
   <td style="text-align:center;">www</td> 
   <td style="text-align:left;">192.168.36.67</td> 
  </tr> 
 </tbody> 
</table>

--------------------

注意：在实验前一定要确保7台机器都可以相互ping通!!

> CentOS7 :: www :: 192.168.36.67

[root@www ~]# yum install httpd -y               
    
    [root@www ~]# echo 'welcome to Tuvia`s home !' > /var/www/html/index.html           # 自行编辑一个网页内容；便于识别
    # 最好到Windows浏览器打开192.168.36.67查看一下该网页进行验证

> CentOS6 :: Clint :: 192.168.36.6
> 
> > 验证

[root@localhost ~]# vim /etc/sysconfig/network-scripts/ifcfg-eth0
    DEVICE=eth0
    BOOTPROTO=static
    IPADDR=192.168.36.6
    NETMASK=255.255.255.0
    DNS1=192.168.36.7                               ## 指定DNS ##
    ONBOOT=yes
                ：wq
    
    [root@localhost ~]# service network restart
    Shutting down interface eth0:  Device state: 3 (disconnected)
                                                               [  OK  ]
    Shutting down interface eth1:                              [  OK  ]
    Shutting down loopback interface:                          [  OK  ]
    Bringing up loopback interface:                            [  OK  ]
    
    [root@localhost ~]# cat /etc/resolv.conf
    # Generated by NetworkManager
    nameserver 192.168.36.7
    
    [root@localhost ~]# curl 192.168.36.67
    welcome to Tuvia`s home !

> CentOS7 :: Master :: 192.168.36.37

[root@severus ~]# yum install bind -y
    
    [root@severus ~]# vim /etc/named.conf 
           listen-on port 53 { 127.0.0.1; };           #找到这行将这行注释掉
            allow-query     { localhost; };             #找到这行将这行注释掉
    
    //      listen-on port 53 { 127.0.0.1; };           #注释；即无效
    //      allow-query     { localhost; };             #注释；即无效
    
            allow-transfer {192.168.36.47;};            #并在options中添加这行；意味只允许47同步数据
    
                        :wq
    
    [root@severus ~]#rndc reload
    [root@severus ~]# vim /etc/named.rfc1912.zones 
    //
    zone "magedu.com" {             #在//下添加此内容
        type master;
        file "magedu.com.zone";
    };
                        :wq
    
    [root@severus ~]# cd /var/named
    [root@severus named]# ls
    data  dynamic  magedu.com.zone  named.ca  named.empty  named.localhost  named.loopback  slaves
    
    [root@severus named]# vim magedu.com.zone
    $TTL 1D
    @ IN    SOA   ns1 adm.magedu.com. ( 1 1H 10M 1D 3H )
            NS ns1
            NS ns2
    ns1 A 192.168.36.37
    ns2 A 192.168.36.47
    www A 192.168.36.67
    [root@severus named]# ll
    total 20
    drwxrwx--- 2 named named   23 Apr 23 00:09 data
    drwxrwx--- 2 named named   31 Apr 23 09:34 dynamic
    -rw-r--r-- 1 root  root   137 Apr 23 11:16 magedu.com.zone
    -rw-r----- 1 root  named 2281 May 22  2017 named.ca
    -rw-r----- 1 root  named  152 Dec 15  2009 named.empty
    -rw-r----- 1 root  named  152 Jun 21  2007 named.localhost
    -rw-r----- 1 root  named  168 Dec 15  2009 named.loopback
    drwxrwx--- 2 named named    6 Oct 31 08:29 slaves
    [root@severus named]# chgrp named magedu.com.zone 
    [root@severus named]# chmod 640 magedu.com.zone 
    [root@severus named]# systemctl start named

> CentOS6 :: Clint :: 192.168.36.6
> 
> > 验证

[root@localhost ~]# dig www.magedu.com @192.168.36.37
    
    ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.62.rc1.el6 <<>> www.magedu.com @192.168.36.37
    ;; global options: +cmd
    ;; Got answer:
    ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 1068
    ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 2
    
    ;; QUESTION SECTION:
    ;www.magedu.com.            IN  A
    
    ;; ANSWER SECTION:
    www.magedu.com.     86400   IN  A   192.168.36.67           #
    
    ;; AUTHORITY SECTION:
    magedu.com.     86400   IN  NS  ns1.magedu.com.         #
    magedu.com.     86400   IN  NS  ns2.magedu.com.         #
    
    ;; ADDITIONAL SECTION:
    ns1.magedu.com.     86400   IN  A   192.168.36.37           #
    ns2.magedu.com.     86400   IN  A   192.168.36.47           #
    
    ;; Query time: 1 msec
    ;; SERVER: 192.168.36.37#53(192.168.36.37)
    ;; WHEN: Tue Apr 23 04:23:11 2019
    ;; MSG SIZE  rcvd: 116

> CentOS7 :: Slaves :: 192.168.36.47

[18:24:54 root@severus ~]#yum install bind -y
    [19:25:07 root@severus ~]#vim /etc/named.conf 
    
            listen-on port 53 { 127.0.0.1; };           #找到这行将这行注释掉
            allow-query     { localhost; };             #找到这行将这行注释掉
    
    //      listen-on port 53 { 127.0.0.1; };           #注释；即无效
    //      allow-query     { localhost; };             #注释；即无效
    
            allow-transfer {none;};                     #并在options中添加这行；意为不允许任何人同步数据
    
                        :wq
    
    [19:27:01 root@severus ~]#vim /etc/named.rfc1912.zones 
    //
    zone "magedu.com" {                                 #在//下添加此内容
        type slave;
        masters {192.168.36.37;};
        file "slaves/magedu.com.zone";
    };
                        :wq
    
    [19:32:13 root@severus ~]#systemctl start named
    [19:34:06 root@severus ~]#ll /var/named/slaves/
    total 4
    -rw-r--r--. 1 named named 304 Apr 23 17:39 magedu.com.zone          #同步来的数据库

> CentOS7 :: comDNS :: 192.168.36.27

[17:11:37 root@severus ~]#yum install bind -y
    [17:12:18 root@severus ~]#vim /etc/named.conf 
    
            listen-on port 53 { 127.0.0.1; };           #找到这行将这行注释掉
            allow-query     { localhost; };             #找到这行将这行注释掉
    
    //      listen-on port 53 { 127.0.0.1; };           #注释；即无效
    //      allow-query     { localhost; };             #注释；即无效
    
                        :wq
    
    [17:12:50 root@severus ~]#vim /etc/named.rfc1912.zones 
    //
    zone "com" {
        type master;
        file "com.zone";
    };
                        :wq
    
    [17:14:21 root@severus named]#vim com.zone
    $TTL 1D
    @ IN SOA ns1 admin.magedu.com. (1 1D 1H 1W 3D )
                 NS ns1
    magedu       NS mageduns1
    magedu       NS mageduns2
    ns1  A  192.168.36.27
    mageduns1 A 192.168.36.37
    mageduns2 A 192.168.36.47
                        :wq
    
    [17:16:58 root@severus named]#systemctl start named

> CentOS6 :: Clint ::192.168.36.6
> 
> > 验证

[root@localhost ~]# dig www.magedu.com @192.168.36.27
    
    ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.62.rc1.el6 <<>> www.magedu.com @192.168.36.27
    ;; global options: +cmd
    ;; Got answer:
    ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 60127
    ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 2
    
    ;; QUESTION SECTION:
    ;www.magedu.com.            IN  A
    
    ;; ANSWER SECTION:
    www.magedu.com.     86400   IN  A   192.168.36.67           #
    
    ;; AUTHORITY SECTION:
    magedu.com.     86400   IN  NS  mageduns1.com.          #
    magedu.com.     86400   IN  NS  mageduns2.com.          #
    
    ;; ADDITIONAL SECTION:
    mageduns1.com.      86400   IN  A   192.168.36.37           #
    mageduns2.com.      86400   IN  A   192.168.36.47           #
    
    ;; Query time: 3 msec
    ;; SERVER: 192.168.36.27#53(192.168.36.27)
    ;; WHEN: Tue Apr 23 04:41:49 2019
    ;; MSG SIZE  rcvd: 128

> CentOS :: RootDNS :: 192.168.36.17

[root@severus ~]# yum install bind -y
    [root@severus ~]# vim /etc/named.conf 
    
            listen-on port 53 { 127.0.0.1; };           #找到这行将这行注释掉
            allow-query     { localhost; };             #找到这行将这行注释掉
    
    //      listen-on port 53 { 127.0.0.1; };           #注释；即无效
    //      allow-query     { localhost; };             #注释；即无效
    
    zone "." IN {                                       #找到此内容
            type hint;
            file "named.ca";
    };
    
    zone "." IN {                                       #改为此内容
            type master;
            file "root.zone";
    
                        :wq
    
    [root@severus ~]# cd /var/named
    [root@severus named]# vim root.zone
    $TTL 1D
    @ IN SOA ns1 admin.magedu.com. (1 1D 1H 1W 3D )
                 NS ns1
    com          NS comns
    ns1  A  192.168.36.17
    comns A 192.168.36.27
                        :wq
    
    [root@severus named]# systemctl start named

> CentOS6 :: Clint ::192.168.36.6
> 
> > 验证

[root@localhost ~]# dig www.magedu.com @192.168.36.17
    
    ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.62.rc1.el6 <<>> www.magedu.com @192.168.36.17
    ;; global options: +cmd
    ;; Got answer:
    ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 38615
    ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 2
    
    ;; QUESTION SECTION:
    ;www.magedu.com.            IN  A
    
    ;; ANSWER SECTION:
    www.magedu.com.     86400   IN  A   192.168.36.67           #
    
    ;; AUTHORITY SECTION:
    magedu.com.     86400   IN  NS  mageduns1.com.          #
    magedu.com.     86400   IN  NS  mageduns2.com.          #
    
    ;; ADDITIONAL SECTION:
    mageduns1.com.      86400   IN  A   192.168.36.37           #
    mageduns2.com.      86400   IN  A   192.168.36.47           #
    
    ;; Query time: 3 msec
    ;; SERVER: 192.168.36.17#53(192.168.36.17)
    ;; WHEN: Tue Apr 23 04:49:51 2019
    ;; MSG SIZE  rcvd: 128

> CentOS7 :: LDNS :: 192.168.36.7

[root@severus ~]# yum install bind -y
    [root@severus ~]# vim /etc/named.conf 
    
            listen-on port 53 { 127.0.0.1; };           #找到这行将这行注释掉
            allow-query     { localhost; };             #找到这行将这行注释掉
    
    //      listen-on port 53 { 127.0.0.1; };           #注释；即无效
    //      allow-query     { localhost; };             #注释；即无效
    
            dnssec-enable yes;                          #找到这两行
            dnssec-validation yes;
    
            dnssec-enable no;                           #将yes改为no
            dnssec-validation no;
    
                            :wq
    
    [root@severus ~]# vim /var/named/named.ca
    .                       518400  IN      NS      a.root-servers.net.
    a.root-servers.net.     3600000 IN      A       192.168.36.17
    
    [root@severus ~]# systemctl start named
    [root@severus ~]# rndc flush                        #清除缓存

> CentOS7 :: LDNS :: 192.168.36.17

[root@severus ~]# rndc flush                        #清除缓存

> CentOS7 :: LDNS :: 192.168.36.27

[root@severus ~]# rndc flush                        #清除缓存

> CentOS7 :: LDNS :: 192.168.36.37

[root@severus ~]# rndc flush                        #清除缓存

> CentOS7 :: LDNS :: 192.168.36.47

[root@severus ~]# rndc flush                        #清除缓存

> CentOS6 :: Clint :: 192.168.36.6
> 
> > 验证

[root@localhost ~]# dig www.magedu.com
    
    ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.62.rc1.el6 <<>> www.magedu.com
    ;; global options: +cmd
    ;; Got answer:
    ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 17145
    ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 2
    
    ;; QUESTION SECTION:
    ;www.magedu.com.            IN  A
    
    ;; ANSWER SECTION:
    www.magedu.com.     86400   IN  A   192.168.36.67               #
    
    ;; AUTHORITY SECTION:
    magedu.com.     86400   IN  NS  ns2.magedu.com.             #
    magedu.com.     86400   IN  NS  ns1.magedu.com.             #
    
    ;; ADDITIONAL SECTION:
    ns1.magedu.com.     86400   IN  A   192.168.36.37               #
    ns2.magedu.com.     86400   IN  A   192.168.36.47               #
    
    ;; Query time: 7 msec
    ;; SERVER: 192.168.36.7#53(192.168.36.7)
    ;; WHEN: Tue Apr 23 05:00:36 2019
    ;; MSG SIZE  rcvd: 116

--------------------

总结：
                            此实验重点在于理解；步骤繁琐重复细节较多；切勿急于求成

转载于:https://blog.51cto.com/14284458/2383166