关于默认路由的各种疑问？？？为什么不通啊？？？

boywf87

有一个疑问，为什么R1 ping 不通 R4的接口IP 3.3.3. 3？？比较奇怪的居然能PING 通3.3.3.1
这个实验是做的默认路由

连接图 ： 1.1.1.1(R1)  -- 1.1.1.2 (R2)
                 2.2.2.1(R2) -- 2.2.2. 2(R3)
                3.3.3.1(R3)--- 3.3.3.3 (R4）

测试结果如下：

R1#ping 3.3.3.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 3.3.3.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/48/116 ms
R1#ping 3.3.3.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 3.3.3.3, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)


各路由器 路由表如下：
R1#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       o - ODR, P - periodic downloaded static route
Gateway of last resort is 1.1.1.2 to network 0.0.0.0
     1.0.0.0/24 is subnetted, 1 subnets
C       1.1.1.0 is directly connected, Serial0/0
S*   0.0.0.0/0 [1/0] via 1.1.1.2

R2#sh ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       o - ODR, P - periodic downloaded static route
Gateway of last resort is 2.2.2.2 to network 0.0.0.0
     1.0.0.0/24 is subnetted, 1 subnets
C       1.1.1.0 is directly connected, Serial0/0
     2.0.0.0/24 is subnetted, 1 subnets
C       2.2.2.0 is directly connected, Serial0/1
S*   0.0.0.0/0 [1/0] via 2.2.2.2
               [1/0] via 1.1.1.1

R3#sh ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       o - ODR, P - periodic downloaded static route
Gateway of last resort is 3.3.3.3 to network 0.0.0.0
     2.0.0.0/24 is subnetted, 1 subnets
C       2.2.2.0 is directly connected, Serial0/1
     3.0.0.0/24 is subnetted, 1 subnets
C       3.3.3.0 is directly connected, Serial0/0
S*   0.0.0.0/0 [1/0] via 3.3.3.3
               [1/0] via 2.2.2.1

R4#sh ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       o - ODR, P - periodic downloaded static route
Gateway of last resort is 3.3.3.1 to network 0.0.0.0
     3.0.0.0/24 is subnetted, 1 subnets
C       3.3.3.0 is directly connected, Serial0/0
S*   0.0.0.0/0 [1/0] via 3.3.3.1

boywf87

在线跪求真相~~~~~~~~~~~~~~~~~~

xiegui

看看配置文件

ziyouhaiyang

R3上没有去往1.1.1.1的路由，在R3上添加一条静态路由：
ip route 1.1.1.1 255.255.255.255 2.2.2.1
应该就可以了

boywf87

ziyouhaiyang 发表于 2012-8-18 20:48
R3上没有去往1.1.1.1的路由，在R3上添加一条静态路由：
ip route 1.1.1.1 255.255.255.255 2.2.2.1
应该就 ...

和这个没关系 我试了 不行。。。

boywf87

继续啊~~~~~~~~~~~~~

Viben-w

默认路由是吧

zh754267513

在r3上掉包了！ 包可以到达r4 但是在回包的时候掉包了！ 在r3 r2 上做一条静态！ 你可以在r4上debug        看一下！你看下包的走向！

zh754267513

另外楼主你出了个很大的问题！ 只能在边界下放默认路由！ 你这样会出很大的问题的！ 因为有两个默认的时候你猜他会走那条里！ 所以你这个文档的网络设计也存在问题！