• DNS服务以及相关技术


    搭建一个公司内部的DNS

    把地址改成公司内部服务器

    [root@centos8 named]# vim /var/named/named.ca 

    把DNS指向自己内部服务器

    [root@centos8 named]# vim /etc/sysconfig/network-scripts/ifcfg-eth0 
    ​
    BROWSER_ONLY="no"
    BOOTPROTO="static"
    DEFROUTE="yes"
    NAME="eth0"
    DEVICE="eth0"
    ONBOOT="ystatic
    IPADDR="10.0.0.134"
    GATEWAY="10.0.0.2"
    DNS1="127.0.0.1"

    然后重启服务

    SOA记录的建造#主机服务器

    1.首先建立一个xxx.org这样的域 用来解析这个域里所有的资源记录的信息

    参考文件:/var/named/named.localhost

    [root@centos8 ~]# cat /var/named/named.localhost 
    $TTL 1D
    @    IN SOA    @ rname.invalid. (                 #主DNS服务器的名称(本域);邮箱
                        0    ; serial               #数据库版本号
                        1D    ; refresh              #同步的时间间隔
                        1H    ; retry                #重置时间
                        1W    ; expire               #过期时长
                        3H )    ; minimum          #否定结果的缓存时长
        NS    @
        A    127.0.0.1
        AAAA    ::1
    name [TTL] IN rr_type value     #格式

    习惯用域名加.zone 作为文件命名方式

    [root@centos8 named]# vim zty123.local.zone
    $TTL 86400
    @               IN SOA  master  admin.zty123.com. ( 1  3600 10M  3D 1D )
                       NS   master
    
    master          A       10.0.0.134
    www             A       10.0.0.100
    ~                                                                                                                                  
    ~                                                                                                                                  
    ~      

    更改bind配置文件

    [root@centos8 named]# vim /etc/named.conf 
    
    //
    // named.conf
    //
    // Provided by Red Hat bind package to configure the ISC BIND named(8) DNS
    // server as a caching only nameserver (as a localhost DNS resolver only).
    //
    // See /usr/share/doc/bind*/sample/ for example named configuration files.
    //
    
    options {
            listen-on port 53 { localhost; };      #该主机的每一个IP地址
            listen-on-v6 port 53 { ::1; };
            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";
            secroots-file   "/var/named/data/named.secroots";
            recursing-file  "/var/named/data/named.recursing";
            allow-query     { any; };        

    改权限、属组

    [root@centos8 named]# chmod 640 /var/named/zty123.local.zone 
    [root@centos8 named]# ll
    total 20
    drwxrwx--- 2 named named   23 Sep 14 19:44 data
    drwxrwx--- 2 named named   60 Sep 14 19:44 dynamic
    -rw-r----- 1 root  named 2253 Jul  7 22:14 named.ca
    -rw-r----- 1 root  named  152 Jul  7 22:14 named.empty
    -rw-r----- 1 root  named  152 Jul  7 22:14 named.localhost
    -rw-r----- 1 root  named  168 Jul  7 22:14 named.loopback
    drwxrwx--- 2 named named    6 Jul  7 22:14 slaves
    -rw-r----- 1 root  root   170 Sep 14 19:43 zty123.local.zone
    [root@centos8 named]# chgrp named zty123.local.zone 
    [root@centos8 named]# ll
    total 20
    drwxrwx--- 2 named named   23 Sep 14 19:44 data
    drwxrwx--- 2 named named   60 Sep 14 19:44 dynamic
    -rw-r----- 1 root  named 2253 Jul  7 22:14 named.ca
    -rw-r----- 1 root  named  152 Jul  7 22:14 named.empty
    -rw-r----- 1 root  named  152 Jul  7 22:14 named.localhost
    -rw-r----- 1 root  named  168 Jul  7 22:14 named.loopback
    drwxrwx--- 2 named named    6 Jul  7 22:14 slaves
    -rw-r----- 1 root  named  170 Sep 14 19:43 zty123.local.zone

    随后改配置文件(这是个专门存放区域信息的文件)#直接/etc/named.conf也行

    [root@centos8 named]# cat /etc/named.rfc1912.zones
    // named.rfc1912.zones:
    //
    // Provided by Red Hat caching-nameserver package 
    //
    // ISC BIND named zone configuration for zones recommended by
    // RFC 1912 section 4.1 : localhost TLDs and address zones
    // and https://tools.ietf.org/html/rfc6303
    // (c)2007 R W Franks
    // 
    // See /usr/share/doc/bind*/sample/ for example named configuration files.
    //
    // Note: empty-zones-enable yes; option is default.
    // If private ranges should be forwarded, add 
    // disable-empty-zone "."; into options
    // 
    zone "zty123.local" IN {                  #域名
            type master;
            file "zty123.local.zone";         #主DNS服务器的数据库
    };
    
    
    zone "localhost.localdomain" IN {
        type master;
        file "named.localhost";
        allow-update { none; };
    };
    
    zone "localhost" IN {
        type master;
        file "named.localhost";
        allow-update { none; };
    };
    
    zone "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa" IN {
        type master;
        file "named.loopback";
        allow-update { none; };
    };
    
    zone "1.0.0.127.in-addr.arpa" IN {
        type master;
        file "named.loopback";
        allow-update { none; };
    };
    
    zone "0.in-addr.arpa" IN {
        type master;
        file "named.empty";
        allow-update { none; };
    };

    用名令查DNS错误

    [root@centos8 named]# named-checkzone zty123.local /var/named/zty123.local.zone 
    zone zty123.local/IN: loaded serial 1
    OK

    搭建从服务器(备份服务器)

    下载并安装bind

    改配置文件

    [root@centos8 ~]# vim /etc/named.conf 
    
    //
    // named.conf
    //
    // Provided by Red Hat bind package to configure the ISC BIND named(8) DNS
    // server as a caching only nameserver (as a localhost DNS resolver only).
    //
    // See /usr/share/doc/bind*/sample/ for example named configuration files.
    //
    
    options {
    //      listen-on port 53 { 127.0.0.1; };              #注释
            listen-on-v6 port 53 { ::1; };
            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";
            secroots-file   "/var/named/data/named.secroots";
            recursing-file  "/var/named/data/named.recursing";
    //      allow-query     { localhost; };                 #注释
    [root@centos8 ~]# vim /etc/named.rfc1912.zones 
    
    // named.rfc1912.zones:
    //
    // Provided by Red Hat caching-nameserver package
    //
    // ISC BIND named zone configuration for zones recommended by
    // RFC 1912 section 4.1 : localhost TLDs and address zones
    // and https://tools.ietf.org/html/rfc6303
    // (c)2007 R W Franks
    //
    // See /usr/share/doc/bind*/sample/ for example named configuration files.
    //
    // Note: empty-zones-enable yes; option is default.
    // If private ranges should be forwarded, add
    // disable-empty-zone "."; into options
    //
    
    zone "zty123.local" {                                    #域名
            type slave;                                        #从服务器名
            master {10.0.0.134};                            #主服务器地址
            file "slaves/zty123.local.zone.slave";            #表示从主服务器复制过来的文件
    };                                                        #加入

    同步 rndc reload

    更新的时候 现在从服务器还没有更新文件 需要在主服务器加上从服务器并更新版本号(推) 或者从服务器主动去拉

     

    安全

    在没有安全设置的情况下 不更改主服务器任何设置 随意一个主机都能成为主服务器的从服务器 想抓就能抓

    [10:41:18 root@centos7 ~]#dig -t axfr zty123.local @10.0.0.134
    
    ; <<>> DiG 9.11.4-P2-RedHat-9.11.4-16.P2.el7 <<>> -t axfr zty123.local @10.0.0.134
    ;; global options: +cmd
    zty123.local.        86400    IN    SOA    master.zty123.local. admin.zty123.com. 2 3600 600 259200 86400
    zty123.local.        86400    IN    NS    master.zty123.local.
    zty123.local.        86400    IN    NS    slave.zty123.local.
    *.zty123.local.        86400    IN    A    10.0.0.100
    k8s-master.zty123.local. 86400    IN    A    1.1.1.1
    master.zty123.local.    86400    IN    A    10.0.0.134
    web.zty123.local.    86400    IN    A    10.0.0.100
    www.zty123.local.    86400    IN    CNAME    web.zty123.local.
    zty123.local.        86400    IN    SOA    master.zty123.local. admin.zty123.com. 2 3600 600 259200 86400
    ;; Query time: 0 msec
    ;; SERVER: 10.0.0.134#53(10.0.0.134)
    ;; WHEN: Tue Sep 15 11:12:42 CST 2020
    ;; XFR size: 9 records (messages 1, bytes 269)

    在主服务器上更改配置文件

    [root@centos8 named]# vim /etc/named.conf 
    
    //
    // named.conf
    //
    // Provided by Red Hat bind package to configure the ISC BIND named(8) DNS
    // server as a caching only nameserver (as a localhost DNS resolver only).
    //
    // See /usr/share/doc/bind*/sample/ for example named configuration files.
    //
    
    options {
    //      listen-on port 53 { localhost; };
            listen-on-v6 port 53 { ::1; };
            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";
            secroots-file   "/var/named/data/named.secroots";
            recursing-file  "/var/named/data/named.recursing";
    //      allow-query     { any; };
            allow-transfer {10.0.0.100;};                #指定从服务器的IP地址
            /* 
    [root@centos8 named]# rndc reload                   #同步

    现在主服务器抓不到了 但是从服务器还能抓到 所以改从服务器的配置文件

    [root@centos8 ~]# vim /etc/named.conf 
    
    //
    // named.conf
    //
    // Provided by Red Hat bind package to configure the ISC BIND named(8) DNS
    // server as a caching only nameserver (as a localhost DNS resolver only).
    //
    // See /usr/share/doc/bind*/sample/ for example named configuration files.
    //
    
    options {
    //      listen-on port 53 { 127.0.0.1; };
            listen-on-v6 port 53 { ::1; };
            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";
            secroots-file   "/var/named/data/named.secroots";
            recursing-file  "/var/named/data/named.recursing";
    //      allow-query     { localhost; };
            allow-transsfer {none;};                    #不让任何人传输
    [root@centos8 named]# rndc reload                   #同步

    子域

    这是真正的独立域 (访问量少的子域父域可以在一个服务器上 jl.zty123.local A 10.0.0.134)

    在同一台机上 同时有父域子域

    [root@centos8 named]# vim /etc/named.rfc1912.zones 
    
    // named.rfc1912.zones:
    //
    // Provided by Red Hat caching-nameserver package
    //
    // ISC BIND named zone configuration for zones recommended by
    // RFC 1912 section 4.1 : localhost TLDs and address zones
    // and https://tools.ietf.org/html/rfc6303
    // (c)2007 R W Franks
    //
    // See /usr/share/doc/bind*/sample/ for example named configuration files.
    //
    // Note: empty-zones-enable yes; option is default.
    // If private ranges should be forwarded, add
    // disable-empty-zone "."; into options
    //
    zone "zty123.local" IN {
            type master;
            file "zty123.local.zone";
    };
    
    zone "jl.zty123.local" IN {                                #这是新加的吉林子域
            type master;
            file "jl.zty123.local.zone";
    };

    可以改一个文件当子域的配置文件

    [root@centos8 named]# cp -p zty123.local.zone jl.zty123.local.zone
    [root@centos8 named]# vim jl.zty123.local.zone 
    
    $TTL 86400
    @               IN SOA  master  admin.zty123.com. ( 2  3600 10M  3D 1D )
                       NS   master
    
    master          A       10.0.0.134
    www             A       2.2.2.2
    [root@centos8 named]# named-checkzone jl.zty123.local jl.zty123.local.zone 
    zone jl.zty123.local/IN: loaded serial 2
    OK                                        #检查一下语法
    
    [root@centos8 named]# rndc reload                   #重新加载

    找个机器解析一下

    [20:13:59 root@centos6 ~]$dig www.jl.zty123.local
    
    ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.68.rc1.el6_10.7 <<>> www.jl.zty123.local
    ;; global options: +cmd
    ;; Got answer:
    ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 44917
    ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 1
    
    ;; QUESTION SECTION:
    ;www.jl.zty123.local.        IN    A
    
    ;; ANSWER SECTION:
    www.jl.zty123.local.    86400    IN    A    2.2.2.2
    
    ;; AUTHORITY SECTION:
    jl.zty123.local.    86400    IN    NS    master.jl.zty123.local.
    
    ;; ADDITIONAL SECTION:
    master.jl.zty123.local.    86400    IN    A    10.0.0.134
    
    ;; Query time: 1 msec
    ;; SERVER: 10.0.0.134#53(10.0.0.134)
    ;; WHEN: Wed Sep  9 20:57:55 2020
    ;; MSG SIZE  rcvd: 90

    找一台单独的服务器当作子域

    在主服务器做委派 把子域交给单独管理 主服务器不管

    在父服务器上 添加子域

    [root@centos8 named]# vim zty123.local.zone 
    
    $TTL 86400
    @               IN SOA  master  admin.zty123.com. ( 2  3600 10M  3D 1D )
                       NS   master
                      NS    slave
    sz              NS      szns1                    #子域
    szns1           A       10.0.0.136                #子域IP;被委派的管理者
    
    
    master          A       10.0.0.134
    www             CNAME   web
    web             A       10.0.0.100
    *               A       10.0.0.100
    k8s-master      A       1.1.1.1
    ~  
    [root@centos8 named]# rndc reload 

    在子服务器上

    [root@centos8 ~]# dnf -y install bind;systemctl enable --now named
    [root@centos8 ~]# vim /etc/named.conf 
    
    //
    // named.conf
    //
    // Provided by Red Hat bind package to configure the ISC BIND named(8) DNS
    // server as a caching only nameserver (as a localhost DNS resolver only).
    //
    // See /usr/share/doc/bind*/sample/ for example named configuration files.
    //
    
    options {
    //      listen-on port 53 { 127.0.0.1; };        #注释
            listen-on-v6 port 53 { ::1; };
            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";
            secroots-file   "/var/named/data/named.secroots";
            recursing-file  "/var/named/data/named.recursing";
    //      allow-query     { localhost; };            #注释
    [root@centos8 ~]# vim /etc/named.rfc1912.zones 
    
    // named.rfc1912.zones:
    //
    // Provided by Red Hat caching-nameserver package
    //
    // ISC BIND named zone configuration for zones recommended by
    // RFC 1912 section 4.1 : localhost TLDs and address zones
    // and https://tools.ietf.org/html/rfc6303
    // (c)2007 R W Franks
    //
    // See /usr/share/doc/bind*/sample/ for example named configuration files.
    //
    // Note: empty-zones-enable yes; option is default.
    // If private ranges should be forwarded, add
    // disable-empty-zone "."; into options
    //
    zone "sz.zty123.local"{                             #添加下列几行
            type master;
            file "sz.zty123.local.zone";
    };

    新建

    [root@centos8 ~]# cd /var/named/
    [root@centos8 named]# ls
    data  dynamic  named.ca  named.empty  named.localhost  named.loopback  slaves
    [root@centos8 named]# vim sz.zty123.local.zone
    
    $TTL 1D
    @       IN      SOA  ns1        admin ( 1 1H 10M 1D 1H  )
            NS      ns1
    ns1     A       10.0.0.136
    
    
    www     A       6.6.6.6
    mail    A       7.7.7.7
    [root@centos8 named]# rndc reload 

    这样深圳的DNS服务器就搭好了

    实现DNS转发(缓存服务器)

    [root@centos8 ~]#yum install bind -y
    [root@centos8 ~]#vim /etc/named.conf      #注释掉两行
    // listen-on port 53 { 127.0.0.1; };
    // allow-query { localhost; };
    
    forward first;
    forwarders { 10.0.0.134;};             #关闭dnsec功能
    
    dnssec-enable no;
    dnssec-validation no;
    [root@centos8 ~]#systemctl start named                     #第一次启动服务
    [root@centos8 ~]#rndc reload                               #不是第一次启动服务

    实现主DNS服务器

     

    [root@centos8 ~]#yum install bind -y
    [root@centos8 ~]#vim /etc/named.conf
    #注释掉两行
    // listen-on port 53 { 127.0.0.1; };
    // allow-query { localhost; };
    vim /etc/named.rfc1912.zones
    #加上下面这段
    zone "magedu.org" {
        type master;
        file "magedu.org.zone";
    };
    [root@centos8 ~]# cp -p /var/named/named.localhost /var/named/magedu.org.zone
    #如果没有-p,需要改权限。chgrp named magedu.org.zone
    [root@centos8 ~]# vim /var/named/magedu.org.zone
    $TTL 1D
    @     IN     SOA     master admin.magedu.org. (
                            2019042214 ; serial
                            1D ; refresh
                            1H ; retry
                            1W ; expire
                            3H ) ; minimum
                    NS         master
    master             A         10.0.0.135
    www                CNAME    websrv                        #web服务器地址
    websrv             A         10.0.0.129               
    [root@centos8 ~]#systemctl start named
    [root@centos8 ~]#rndc reload

    实现web服务

    #安装http服务
    [root@centos8 ~]#yum install httpd
    #配置主页面
    [root@centos8 ~]#echo www.zty123.org > /var/www/html/index.html
    #启动服务
    [root@centos8 ~]#systemctl start httpd

    搭建DNS实现internet dns架构

    环境要求:8台主机

    1、DNS客户端:10.0.0.6/24

    2、本地DNS服务器(只缓存):10.0.0.8/24

    3、转发目标DNS服务器:10.0.0.18/24

    4、根DNS服务器:10.0.0.28/24

    5、org域DNS服务器:10.0.0.38/24

    6、magedu.org域主DNS服务器:10.0.0.48/24

    7、magedu.org域从DNS服务器:10.0.0.58/24

    8、www.magedu.org的WEB服务器:10.0.0.68/24

     

    answer:

    把每个主机的ip以及DNS改成相应的要求

    客户端centos6

    [root@centos6 ~]#vim /etc/sysconfig/network-scripts/ifcfg-eth0
    NAME=eth0
    DEVICE=eth0
    BOOTPROTO=static
    IPADDR=10.0.0.6
    NETMASK=255.255.255.0
    DNS1=10.0.0.8
    ONBOOT=yes
    service network restart

    在centos7上实现web服务

    [root@centos6 ~]#yum install httpd
    [root@centos6 ~]#echo www.magedu.org > /var/www/html/index.html
    [root@centos6 ~]#systemctl start httpd

    magedu.org域主DNS服务

    [root@centos8 ~]#yum install bind -y
    [root@centos8 ~]#vim /etc/named.conf
    #注释掉下面两行
    //         listen-on port 53 { 127.0.0.1; };
    //         allow-query { localhost; };
    
    allow-transfer { 10.0.0.58;};
    
    [root@centos8 ~]#vim /etc/named.rfc1912.zones
    
    zone "magedu.org" {                                        #加上这段
    type master;
    file "magedu.org.zone";
    };                
    
    [root@centos8 ~]#vim /var/named/magedu.org.zone
    
    $TTL 1D
    @             IN     SOA         master     admin.magedu.org. ( 1 1D 1H 1W 3H ) 
                                NS         master
                                NS         slave
    master                         A         10.0.0.48
    slave                         A         10.0.0.58
    www                         A         10.0.0.68
    [root@centos8 ~]#chgrp named /var/named/magedu.org.zone   #改属组
    
    [root@centos8 ~]#systemctl start named

    实现magedu.org域的从DNS服务

    [root@centos8 ~]#yum -y install bind 
    [root@centos8 ~]#vim /etc/named.conf
    // listen-on port 53 { 127.0.0.1; };         #注释掉
    // allow-query { localhost; };               #注释掉
    
    allow-transfer { none;};                    #改成none
    [root@centos8 ~]#vim /etc/named.rfc1912.zones
    
    zone "magedu.org" {                                                    #添加这段
    type slave;
    masters { 10.0.0.48;};
    file "slaves/magedu.org.slave";
    }; 
    [root@centos8 ~]#systemctl start named
    [root@centos8 ~]#ls /var/named/slaves/magedu.org.slave    #查看区域数据库文件是否生成

    实现org域的主DNS服务器

    [root@centos8 ~]#yum install bind -y
    [root@centos8 ~]#vim /etc/named.conf
    #注释掉两行
    //         listen-on port 53 { 127.0.0.1; };
    //         allow-query { localhost; };
    
    [root@centos8 ~]#vim /etc/named.rfc1912.zones
    #加上这段
    zone "org" {
            type master;
            file "org.zone";
    };
    [root@centos8 ~]#vim /var/named/org.zone
    $TTL 1D
    @                 IN SOA         master         admin.magedu.org. ( 1 1D 1H 1W 3D )
                                NS             master
    magedu                         NS             mageduns1
    magedu                         NS             mageduns2
    master                         A             10.0.0.38
    mageduns1                     A             10.0.0.48
    mageduns2                     A             10.0.0.58
    
    [root@centos8 ~]#chgrp named /var/named/org.zone
    systemctl start named

    实现根域的主DNS服务器

    [root@centos8 ~]#yum install bind -y
    [root@centos8 ~]#vim /etc/named.conf
    #注释掉两行,第13行和第21行
    // listen-on port 53 { 127.0.0.1; };
    // allow-query { localhost; };
    #将下面行改为:
    zone "." IN {
            type master;
            file "root.zone";
    };
    [root@centos8 ~]#vim /var/named/root.zone
    $TTL 1D
    @         IN SOA         master admin.magedu.org. ( 1 1D 1H 1W 3D )
                        NS         master
    org                 NS         orgns
    master                 A         10.0.0.28
    orgns                 A         10.0.0.38
    [root@centos8 ~]#chgrp named /var/named/root.zone
    [root@centos8 ~]#chmod 640 /var/named/root.zone

    实现转发目标的DNS服务器

    [root@centos8 ~]#yum install bind -y
    [root@centos8 ~]#vim /etc/named.conf
    //         listen-on port 53 { 127.0.0.1; };
    //         allow-query { localhost; };
            dnssec-enable no;
            dnssec-validation no
    [root@centos8 ~]#vim /var/named/named.ca
    .                     518400         IN         NS         a.root-servers.net.
    a.root-servers.net. 3600000     IN         A         10.0.0.28
    [root@centos8 ~]#systemctl start named

    实现本地只缓存DNS服务器

    [root@centos8 ~]#yum install bind -y
    [root@centos8 ~]#vim /etc/named.conf
    //         listen-on port 53 { 127.0.0.1; };
    //         allow-query { localhost; };
            forward only;
            forwarders { 10.0.0.18;};
            dnssec-enable no;
            dnssec-validation no
    [root@centos8 ~]#systemctl start named

    客户端测试

    [root@centos6 ~]#cat /etc/resolv.conf
    nameserver 10.0.0.8
    [root@centos6 ~]#dig www.magedu.org
    ; <<>> DiG 9.9.4-RedHat-9.9.4-61.el7 <<>> www.magedu.org
    ;; global options: +cmd
    ;; Got answer:
    ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 40755
    ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 3
    ;; OPT PSEUDOSECTION:
    ; EDNS: version: 0, flags:; udp: 4096
    ;; QUESTION SECTION:
    ;www.magedu.org. IN A
    ;; ANSWER SECTION:
    www.magedu.org. 86181 IN A 10.0.0.68
    ;; AUTHORITY SECTION:
    magedu.org. 86181 IN NS ns2.magedu.org.
    magedu.org. 86181 IN NS ns1.magedu.org.
    ;; ADDITIONAL SECTION:
    ns2.magedu.org. 86181 IN A 10.0.0.48
    ns1.magedu.org. 86181 IN A 10.0.0.58
    ;; Query time: 1 msec
    ;; SERVER: 10.0.0.8#53(10.0.0.8)
    ;; WHEN: Fri May 10 17:28:39 CST 2019
    ;; MSG SIZE rcvd: 127 成功
    [root@centos6 ~]#curl www.magedu.org
    [root@centos6 ~]#www.magedu.org
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  • 原文地址:https://www.cnblogs.com/zhangty333/p/13751635.html
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