使用一台RHEL5服务器[Server1]连接A、B、C三个网段,A网段中有一台DHCP服 务器[Server2]。需要在Server1上配置dhcp中继代理,以使Server2能够给三个网段的客户机自动分配IP地址,给A网段的网络打印机绑定永久IP地址。
实验参数如下:
Server1:
eth0: 172.17.17.1/24
eth1: 192.168.1.1/24
eth2: 192.168.2.1/24
Server2:
eth0: 172.17.17.2/24
注意:dhcp也就是Server2上要配置默认网关172.17.17.1
实验环境:一台有三块网卡的RHEL5充当dhcp中继,eth0在vmnet2中,eth1在
vmnet3中,eth2在vmnet5中。分别在三个不同的网段。另一台RHEL5为dhcp服务器 ,eth0的网段在vmnet2中,其中有一台WINDOWS客户机在vmnet3中为动态获取IP, 获得192.168.1.0网段中的IP地址。另一台为linux客户机在vmnet5中为动态获取IP,获得192.168.2.0网段中的ip地址。
1.搭建测试环境
2.配置DHCP(Server2)服务器
vim /etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0
BOOTPROTO=none
HWADDR=00:0c:29:9b:bf:b9
ONBOOT=yes
NETMASK=255.255.255.0
IPADDR=172.17.17.2
GATEWAY=172.17.17.1 //配置DHCP的网关为:中继的和DHCP服务器相连的IP地址
service network restart //重启网络服务
vim /etc/dhcpd.conf
ddns-update-style interim;
ignore client-updates;
default-lease-time 21600; //全局配置
max-lease-time 43200;
subnet 172.17.17.0 netmask 255.255.255.0 {
option routers 172.17.17.1;
option subnet-mask 255.255.255.0;
option time-offset -18000; # Eastern Standard Time
range dynamic-bootp 172.17.17.3 172.17.17.254;
host ns {
hardware ethernet 12:34:56:78:AB:CD;
fixed-address 172.17.17.3;
}
}
subnet 192.168.1.0 netmask 255.255.255.0 {
option routers 192.168.1.1;
option subnet-mask 255.255.255.0;
option time-offset -18000; # Eastern Standard Time
range dynamic-bootp 192.168.1.2 192.168.1.254;
}
subnet 192.168.2.0 netmask 255.255.255.0 {
option routers 192.168.2.1;
option subnet-mask 255.255.255.0;
option time-offset -18000; # Eastern Standard Time
range dynamic-bootp 192.168.2.2 192.168.2.254;
}
3.vim /etc/sysconfig/dhcpd //指定网络接口启动dhcp服务
# Command line options here
DHCPDARGS=eth0
4.service dhcpd restart //重启dhcp服务
5.配置中继代理(Server1)
vim /etc/sysconfig/dhcrelay
INTERFACES=”eth0 eth1 eth2”
DHCPSERVERS=”172.17.17.2”
service dhcrelay restart //重启中继服务
6.中继代理启动网卡转发
vim /etc/sysctl.conf //永久启用(需重启机器)
# Controls IP packet forwarding
net.ipv4.ip_forward = 1
echo 1 > /proc/sys/net/ipv4/ip_forward //临时启用转发
7.测试(winxp)