简单的DDNS

在DNS服务器上:：
放入第一张光盘，执行如下几条命令：

# mount /dev/cdrom

# rpm -ivh /mnt/cdrom/RedHat/RPMS/bind-9.2.1-16.i386.rpm

# cd;eject
然后放入第二张光盘，执行如下命令：

# mount /dev/cdrom

# rpm -ivh /mnt/cdrom/RedHat/RPMS/caching-nameserver-7.2-7.noarch.rpm

# umount /dev/cdrom

# ifconfig
eth0 Link encap:Ethernet HWaddr 00:0C:29:64:23:CF
inet addr:192.168.1.1 Bcast:192.168.1.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1327 errors:0 dropped:0 overruns:0 frame:0
TX packets:1674 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:143095 (139.7 Kb) TX bytes:160234 (156.4 Kb)
Interrupt:10 Base address:0x1080
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:8 errors:0 dropped:0 overruns:0 frame:0
TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:752 (752.0 b) TX bytes:752 (752.0 b)
开始配置DNS:
域名为lab.com
DNS服务器的IP ：192.168.1.1
DHCP服务器的IP: 192.168.1.254
只允许192.168.1.0/24的客户端进行动态注册
1、编辑/etc/named.conf，将内容修改成下面的形式：
options {
directory "/var/named";
};
controls {
inet 127.0.0.1 allow { localhost; } keys { rndckey; };
};
zone "." IN {
type hint;
file "named.ca";
};
zone "localhost" IN {
type master;
file "localhost.zone";
allow-update { none; };
};
zone "0.0.127.in-addr.arpa" IN {
type master;
file "named.local";
allow-update { none; };
};
zone "lab.com" IN {
type master;
file "lab.com.zone";
allow-update { 192.168.1.0/24; };
};
zone "1.168.192.in-addr.arpa" IN {
type master;
file "named.192.168.1";
allow-update { 192.168.1.0/24; };
};
include "/etc/rndc.key";
完成后保存，然后进入数据库目录：

# cd /var/named/
添加如下2个文件，内容如下：
/var/named/lab.com.zone
$TTL 86400
@ 1D IN SOA ns1.lab.com. admin.lab.com. (
42 ; serial (d. adams)
3H ; refresh
15M ; retry
1W ; expiry
1D ) ; minimum
1D IN NS ns1.lab.com.
ns1 1D IN A 192.168.1.1
dhcpserver 1D IN A 192.168.1.254
/var/named/named.192.168.1

# vi named.192.168.1
$TTL 86400
@ IN SOA ns1.lab.com. admin.lab.com. (
1997022700 ; Serial
28800 ; Refresh
14400 ; Retry
3600000 ; Expire
86400 ) ; Minimum
IN NS ns1.lab.com.
1 IN PTR ns1.lab.com.
254 IN PTR dhcpserver.lab.com.

# service named start
进行正/反向测试：

# host ns1.lab.com
ns1.lab.com has address 192.168.1.1

# host dhcpserver.lab.com
dhcpserver.lab.com has address 192.168.1.254

# host 192.168.1.1
1.1.168.192.in-addr.arpa domain name pointer ns1.lab.com.

# host 192.168.1.254
254.1.168.192.in-addr.arpa domain name pointer dhcpserver.lab.com.
OK,DNS服务器配置完成。
2、在DHCP服务器上的配置
前提准备：配置IP地址，安装DHCP服务器软件，在此不再详述，需要的请看DHCP入门篇第一部分 （最简单的DHCP 服务器的架设）
下面是DHCP的配置文件/etc/dhcpd.conf的内容
ddns-update-style interim;
ignore client-updates;
default-lease-time 21600;
max-lease-time 43200;
subnet 192.168.1.0 netmask 255.255.255.0 {
option routers 192.168.1.254;
option subnet-mask 255.255.255.0;
option domain-name "lab.com";
option domain-name-servers 192.168.1.1;
option time-offset -18000; # Eastern Standard Time
range 192.168.1.100 192.168.1.200;
}
启动DHCP服务器(Service dhcpd start)以后，Windows XP机器选择自动获取IP地址，然后可以到ns1.lab.com下执行如下命令查看是否DDNS更新成功:

# ls /var/named/
lab.com.zone localhost.zone named.192.168.1.jnl named.local
lab.com.zone.jnl named.192.168.1 named.ca
如果看见了*.jnl结尾的证明更新成功，直接在Windows里执行:
C:\Documents and Settings\Administrator>nslookup CLASS-FF5BQ3ATB.lab.com
Server: ns1.lab.com
Address: 192.168.1.1
Name: CLASS-FF5BQ3ATB.lab.com
Address: 192.168.1.200
OK,解析成功。