????2.3????eth3
??????????eth3????????192.168.1.0???Σ??????IP?????192.168.1.254?????????????
????# ifconfig eth2 192.168.1.254 netmask 255.255.255.0
??????/etc/sysconfig/network-scripts???μ?ifcfg-eth2????????????￡?

 

DEVICE = eth2
ONBOOT = yes
BROADCAST = 192.168.1.255
NETWORK = 192.168.1.0
NETMASK = 255.255.255.0
IPADDR = 192.168.1.254

????????????????·???
????# route add -net 192.168.1.0 netmask 255.255.255.0
???????????????????????·???????

 

# route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface
172.16.0.0 * 255.255.0.0 U 0 0 0 eth0
10.0.0.0 * 255.0.0.0 U 0 0 0 eth1
192.168.1.0 * 255.255.255.0 U 0 0 0 eth2

????2.4??????·????????
????2.4.1??????·??
???????????????????·??????????·????????е??????????????????????????????????172.16.1.100?????????????????????????????????????????????????????μ???·??????
????# route add default gw 172.16.1.100
????????
????#ip route add default via 172.16.1.100 dev eth0
??????????????·????????????????????

 

# route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface
172.16.0.0 * 255.255.0.0 U 0 0 0 eth0
10.0.0.0 * 255.0.0.0 U 0 0 0 eth1
192.168.1.0 * 255.255.255.0 U 0 0 0 eth2
default 172.16.1.100 0.0.0.0 UG 0 0 0 eth0

????2.4.2????·?????
????????????????????IP?????????????????/proc/sys/net/ipv4???μ?ip_forward????????????????????ip????????
????echo 1 > /proc/sys/net/ipv4/ip_forward
????????
????/etc/sysctl.conf??????e?????????????????????Ч:
????# Controls IP packet forwarding
????net.ipv4.ip_forward = 1
????iptables -t nat -A POSTROUTING -o eth1 -j MASQUERADE
????#iptables -t nat -A POSTROUTING -s 192.168.1.0/255.255.255.0 -o eth1 -j MASQUERADE
?????????????
????-t nat:????NAT???????????????????????μ?????????
????-A POSTROUTIN:????????????????????????????????????NAT??
????-s 192.168.1.0/255.255.255.0:?????NAT???????????????????????
????-o eht0:???????eth0??
????-j MASQUERADE:??????е??α??????????????α???????eth0???????д???
???????????????????????????????????????????????????????????????????????
????????????????????????????????????????
????Iptables??????????????iptables -t nat –nvL????
????????iptables???á?
????/etc/rc.d/init.d/iptables save
???????????????????iptables????д?????/etc/sysconfig/iptables??????
????????iptables???????Ч??
????service iptables restart
????2.4.3 ????????

 

ip route del default
iptables -t filter –nvL
iptables -t nat -nvL
ip route ls
ip route delete 169.254.0.0/16
service iptables save
watch iptables -nvL

????????????·??????????????
??????linux·??????????
?????????????????????????????????????????????
????ping 172.16.1.1
????ping 192.168.1.254
????ping 10.254.254.254
?????????Щ???????ping???????????????????????????????
???????????????????????????????????
????ping 172.16.1.100
?????????????????????????????????
??????192.168.1.0??????????????????????192.168.1.1??
?????????????????????????????? ping 192.168.1.1
????????????????????????????? ping 192.168.1.254
??????????????????10.254.254.99????????????10.0.0.0?????????????? ping 10.254.254.99
?????????????????????????????? ping 172.16.1.100 ????????????·????????????????????????????????