1.在/etc/rc.d/rc.local中加入如下
(1).如果是DHCP直接上网
echo 1 > /proc/sys/net/ipv4/ip_forward
iptables -t nat -A POSTROUTING -o eth0 -s 192.168.1.0/24 -j MASQUERADE
(2).如果是ADSL拨号上网
echo 1 > /proc/sys/net/ipv4/ip_forward
iptables -t nat -A POSTROUTING -o ppp0 -s 192.168.1.0/24 -j MASQUERADE
(3).如果是固定IP
iptables -t nat -A POSTROUTING -o eth0 -s 192.168.1.0/24 -j SNAT -to-source 10.4.40.13（固定IP）
2./etc/network/interfaces文件配置
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).
# The loopback network interface
auto lo
iface lo inet loopback
auto dsl-provider
iface dsl-provider inet ppp
pre-up /sbin/ifconfig eth1 up # line maintained by pppoeconf
provider dsl-provider
auto eth1
iface eth1 inet manual
auto eth0
iface eth0 inet static
address 192.168.1.1
netmask 255.255.255.0
3.配置客户机网卡
iface eth0 inet static
address 192.168.1.3
netmask 255.255.255.0
gateway 192.168.1.1
如果在上面的服务器下再接一个服务器，配置于上面基本相同，例如：
1.同上(略)
2.配置外网的网卡
iface eth0 inet static
address 192.168.1.133
netmask 255.255.255.0
gateway 192.168.1.1 //指定上一台服务器IP
3.配置内网的网卡
iface eth1 inet static
address 192.168.1.134
netmask 255.255.255.0
4.配置其它客户机网卡
iface eth0 inet static
address 192.168.1.135
netmask 255.255.255.0
gateway 192.168.1.133 //网关
