第二地址解决子网不连续问题

• 拓扑图
  
  
  
  
  

  第二地址解决子网不连续问题

  
  
  
  
  • 基本配置
    
    

  Router(config)#hostname R3

  R3(config)#no ip domain-lookup

  R3(config)#line console 0

  R3(config-line)#logging synchronous

  R3(config-line)#exec-timeout 0 0

  R3(config-line)#exit

  网段配置

  R3(config)#int f0/0

  R3(config-if)#ip address 10.33.5.1 255.255.255.240

  R3(config-if)#no shutdown

  R3(config-if)#int f0/

  *Mar 1 00:21:48.355: %LINK-3-UPDOWN: Interface FastEthernet0/0, changed state to up

  R3(config-if)#int f0/1

  R3(config-if)#ip address 192.168.83.244 255.255.255.0

  R3(config-if)#no shutdown

  Ip配置

  R5#show ip int brief

  Interface IP-Address OK? Method Status Protocol

  FastEthernet0/0 192.168.12.195 YES manual up up

  FastEthernet0/1 192.168.83.1 YES manual up up

  Serial1/0 unassigned YES manual down down

  Serial1/1 unassigned YES unset administratively down down

  Serial1/2 unassigned YES unset administratively down down

  Serial1/3 unassigned YES unset administratively down down

  Loopback0 192.168.12.65 YES manual up up

  初始路由表

  R3#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 not set

  C 192.168.83.0/24 is directly connected, FastEthernet0/1

  10.0.0.0/28 is subnetted, 1 subnets

  C 10.33.5.0 is directly connected, FastEthernet0/0

  R5#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 not set

  192.168.12.0/27 is subnetted, 2 subnets

  C 192.168.12.64 is directly connected, Loopback0

  C 192.168.12.192 is directly connected, FastEthernet0/0

  C 192.168.83.0/24 is directly connected, FastEthernet0/1

  R7r#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 not set

  192.168.12.0/27 is subnetted, 1 subnets

  C 192.168.12.192 is directly connected, FastEthernet0/0

  10.0.0.0/20 is subnetted, 1 subnets

  C 10.33.32.0 is directly connected, FastEthernet0/1

  启动rip1

  R3(config)#router rip

  R3(config-router)#version 1

  R3(config-router)#network 10.33.5.0

  R3(config-router)#network 192.168.83.0

  R3(config-router)#exit

  R5(config-router)#version 1

  R5(config-router)#network 192.168.12.195

  R5(config-router)#network 192.168.83.1

  R5(config-router)#network 192.168.12.64

  R5(config-router)#exit

  R7(config)#router rip

  R7(config-router)#version 1

  R7(config-router)#network 192.168.12.195

  R7(config-router)#network 10.33.32.0

  R7(config-router)#exit

  路由表

  R3#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 not set

  R 192.168.12.0/24 [120/1] via 192.168.83.1, 00:00:16, FastEthernet0/1

  C 192.168.83.0/24 is directly connected, FastEthernet0/1

  10.0.0.0/28 is subnetted, 1 subnets

  C 10.33.5.0 is directly connected, FastEthernet0/0

  2条直连路由 1条192.168.12.0的汇总路由（跨网段汇总了）

  192.168.12.64 与 192.168.12.195 汇总成 192.168.12.0 主网段边界汇总

  R5#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 not set

  192.168.12.0/27 is subnetted, 2 subnets

  C 192.168.12.64 is directly connected, Loopback0

  C 192.168.12.192 is directly connected, FastEthernet0/0

  C 192.168.83.0/24 is directly connected, FastEthernet0/1

  R 10.0.0.0/8 [120/1] via 192.168.83.244, 00:00:27, FastEthernet0/1

  [120/1] via 192.168.12.196, 00:00:11, FastEthernet0/0

  3条直连 2条汇总

  10.33.5.1/20 与 10.33.35.1/20 都跨网段汇总

  R7#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 not set

  192.168.12.0/27 is subnetted, 2 subnets

  R 192.168.12.64 [120/1] via 192.168.12.195, 00:00:19, FastEthernet0/0

  C 192.168.12.192 is directly connected, FastEthernet0/0

  R 192.168.83.0/24 [120/1] via 192.168.12.195, 00:00:19, FastEthernet0/0

  10.0.0.0/20 is subnetted, 1 subnets

  C 10.33.32.0 is directly connected, FastEthernet0/1

  设置R7的f0/0为被动接口 经过180s R5的路由表更新

  Gateway of last resort is not set

  192.168.12.0/27 is subnetted, 2 subnets

  C 192.168.12.64 is directly connected, Loopback0

  C 192.168.12.192 is directly connected, FastEthernet0/0

  C 192.168.83.0/24 is directly connected, FastEthernet0/1

  R 10.0.0.0/8 [120/1] via 192.168.83.244, 00:00:10, FastEthernet0/1

  [120/1] via 192.168.12.196, 00:03:05, FastEthernet0/0

  R5#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 not set

  192.168.12.0/27 is subnetted, 2 subnets

  C 192.168.12.64 is directly connected, Loopback0

  C 192.168.12.192 is directly connected, FastEthernet0/0

  C 192.168.83.0/24 is directly connected, FastEthernet0/1

  R 10.0.0.0/8 [120/1] via 192.168.83.244, 00:00:15, FastEthernet0/1

  R5#

  使用辅助地址解决子网不连续问题

  R3上的第二地址 其他不配任何东西

  interface FastEthernet0/1

  ip address 10.33.55.1 255.255.240.0 secondary

  ip address 192.168.83.244 255.255.255.0

  *Mar 1 01:39:34.267: RIP: build update entries - suppressing null update

  原因是因为 在对端接口没有对应的网段地址 所以 f0/1的第二地址起不来

  在R5上的f0/1配置第二地址

  R5路由表前后对比

  C 192.168.12.64 is directly connected, Loopback0

  C 192.168.12.192 is directly connected, FastEthernet0/0

  C 192.168.83.0/24 is directly connected, FastEthernet0/1

  R 10.0.0.0/8 [120/1] via 192.168.83.244, 00:00:27, FastEthernet0/1

  [120/1] via 192.168.12.196, 00:00:11, FastEthernet0/0

  192.168.12.0/27 is subnetted, 2 subnets

  C 192.168.12.64 is directly connected, Loopback0

  C 192.168.12.192 is directly connected, FastEthernet0/0

  C 192.168.83.0/24 is directly connected, FastEthernet0/1

  10.0.0.0/8 is variably subnetted, 3 subnets, 2 masks

  R 10.0.0.0/20 [120/1] via 192.168.83.244, 00:00:18, FastEthernet0/1

  //如果是，接收方使用自己的接口上的掩码匹配路由更新

  R 10.0.0.0/8 [120/1] via 192.168.83.244, 00:00:46, FastEthernet0/1

  [120/1] via 192.168.12.196, 00:00:38, FastEthernet0/0

  C 10.33.48.0/20 is directly connected, FastEthernet0/1

  明显多了2条路由 但是发现没有发带掩码的地址 即是10.33.0.0/20的地址

  原因 没有netwofk 第二网段 即 10.33.48.0 错误 //错误的解释

  原因是配错了R3的F0/0网段的子网掩码

  *Mar 1 02:23:17.603: RIP: build update entries

  *Mar 1 02:23:17.603: subnet 10.33.0.0 metric 1

  这时就会通告10.33.0.0这个子网

  R5 的路由表

  R5# 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 not set

  192.168.12.0/27 is subnetted, 2 subnets

  C 192.168.12.64 is directly connected, Loopback0

  C 192.168.12.192 is directly connected, FastEthernet0/0

  C 192.168.83.0/24 is directly connected, FastEthernet0/1

  10.0.0.0/20 is subnetted, 3 subnets //表示10.0.0.0下面有三个子网 列在下面

  R 10.0.0.0 [120/1] via 192.168.83.244, 00:00:24, FastEthernet0/1

  C 10.33.48.0 is directly connected, FastEthernet0/1

  R 10.33.0.0 [120/1] via 10.33.55.1, 00:00:24, FastEthernet0/1

  全部配完

  192.168.12.0/27 is subnetted, 2 subnets

  C 192.168.12.64 is directly connected, Loopback0

  C 192.168.12.192 is directly connected, FastEthernet0/0

  C 192.168.83.0/24 is directly connected, FastEthernet0/1

  10.0.0.0/20 is subnetted, 5 subnets

  R 10.0.0.0 [120/1] via 192.168.83.244, 00:00:11, FastEthernet0/1

  [120/1] via 192.168.12.196, 00:00:18, FastEthernet0/0

  R 10.33.32.0 [120/1] via 10.33.75.2, 00:00:18, FastEthernet0/0

  C 10.33.48.0 is directly connected, FastEthernet0/1

  R 10.33.0.0 [120/1] via 10.33.55.1, 00:00:12, FastEthernet0/1

  C 10.33.64.0 is directly connected, FastEthernet0/0

  这时候删除R5的f0/1的第二id 查R5的路由表

  C 192.168.12.64 is directly connected, Loopback0

  C 192.168.83.0/24 is directly connected, FastEthernet0/1

  10.0.0.0/8 is variably subnetted, 3 subnets, 2 masks

  R 10.0.0.0/20 [120/1] via 192.168.83.244, 00:01:24, FastEthernet0/1

  R 10.0.0.0/8 [120/1] via 192.168.83.244, 00:00:00, FastEthernet0/1

  R 10.33.0.0/20 [120/1] via 10.33.55.1, 00:01:24, FastEthernet0/1

  遇到的问题

  Ip配置重复，倒置ping不同，改好后全网连通

  
  
  

果断回帖，如果沉了就是我弄沉的很有成就感