五、配置默认路由
实验拓扑：
1、ip地址表：
PC1 ip 192.168.10.2/24
Gateway 192.168.10.1
PC2 ip 192.168.30.2/24
Gateway 192.168.30.1
R1 F0/0 192.168.10.1/24
R1 S2/0 192.168.20.1/24
R2 F0/0 192.168.30.1/24
R2 S2/0 192.168.20.2/24
2、
R1的配置：
R1(config)#interface fastEthernet 0/0 //进入接口模式
R1(config-if)#ip address 192.168.10.1 255.255.255.0 //配置接口地址
R1(config-if)#no shutdown //激活接口
R1(config-if)#ip address 192.168.10.1 255.255.255.0 //配置接口地址
R1(config-if)#no shutdown //激活接口
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
R1(config-if)#exit
R1(config)#interface serial 2/0 //进入接口模式
R1(config-if)#ip address 192.168.20.1 255.255.255.0 //配置接口地址
R1(config-if)#no shutdown //激活接口
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
R1(config-if)#exit
R1(config)#interface serial 2/0 //进入接口模式
R1(config-if)#ip address 192.168.20.1 255.255.255.0 //配置接口地址
R1(config-if)#no shutdown //激活接口
%LINK-5-CHANGED: Interface Serial2/0, changed state to down
R1(config-if)#exit
R1(config)#ip route
R1(config)#ip route 0.0.0.0 0.0.0.0 192.168.20.2 //配置默认路由R2的S2/0
R1(config)#exit
%SYS-5-CONFIG_I: Configured from console by console
R1#write
Destination filename [startup-config]?
Building configuration...
[OK]
R1#
R1(config-if)#exit
R1(config)#ip route
R1(config)#ip route 0.0.0.0 0.0.0.0 192.168.20.2 //配置默认路由R2的S2/0
R1(config)#exit
%SYS-5-CONFIG_I: Configured from console by console
R1#write
Destination filename [startup-config]?
Building configuration...
[OK]
R1#
R2的配置：
R2(config)#interface fastEthernet 0/0 //进入接口模式
R2(config-if)#ip address 192.168.30.1 255.255.255.0 //配置接口地址
R2(config-if)#no shutdown //激活接口
R2(config-if)#ip address 192.168.30.1 255.255.255.0 //配置接口地址
R2(config-if)#no shutdown //激活接口
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
R2(config-if)#exit
R2(config)#interface serial 2/0 //进入接口模式
R2(config-if)#ip address 192.168.20.2 255.255.255.0 //配置接口地址
R2(config-if)#clock rate 64000 //设置时钟频率，R1和R2哪端是DCE端就在哪端设时钟，查看命令#show controllers serial 2/0
R2(config-if)#no shutdown
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
R2(config-if)#exit
R2(config)#interface serial 2/0 //进入接口模式
R2(config-if)#ip address 192.168.20.2 255.255.255.0 //配置接口地址
R2(config-if)#clock rate 64000 //设置时钟频率，R1和R2哪端是DCE端就在哪端设时钟，查看命令#show controllers serial 2/0
R2(config-if)#no shutdown
%LINK-5-CHANGED: Interface Serial2/0, changed state to up
R2(config-if)#
%LINEPROTO-5-UPDOWN: Line protocol on Interface Serial2/0, changed state to up
R2(config-if)#exit
R2(config)#ip route 0.0.0.0 0.0.0.0 192.168.20.1 //配置默认路由R1的S2/0
R2(config)#exit
%SYS-5-CONFIG_I: Configured from console by console
R2#write
Destination filename [startup-config]?
Building configuration...
[OK]
R2#
R2(config-if)#
%LINEPROTO-5-UPDOWN: Line protocol on Interface Serial2/0, changed state to up
R2(config-if)#exit
R2(config)#ip route 0.0.0.0 0.0.0.0 192.168.20.1 //配置默认路由R1的S2/0
R2(config)#exit
%SYS-5-CONFIG_I: Configured from console by console
R2#write
Destination filename [startup-config]?
Building configuration...
[OK]
R2#
验证配置：
PC1去ping PC2
PC>ping 192.168.30.2
Pinging 192.168.30.2 with 32 bytes of data:
Request timed out.
Reply from 192.168.30.2: bytes=32 time=129ms TTL=126
Reply from 192.168.30.2: bytes=32 time=106ms TTL=126
Reply from 192.168.30.2: bytes=32 time=106ms TTL=126
Reply from 192.168.30.2: bytes=32 time=129ms TTL=126
Reply from 192.168.30.2: bytes=32 time=106ms TTL=126
Reply from 192.168.30.2: bytes=32 time=106ms TTL=126
通了，说明默认路由实验成功！！！！！！！！！！
