IP : 增强的内部网关路由选择协议 (EIGRP)

防止重复的 EIGRP 路由器 ID

2016 年 10 月 24 日 - 机器翻译
其他版本: PDFpdf | 英语 (2015 年 8 月 22 日) | 反馈


目录


简介

重复的增强的内部网关路由选择协议(EIGRP)路由器ID能引起问题由于EIGRP外部路由的再分配。本文解释问题并且提供正确的配置防止它。

EIGRP路由器ID通常选择与开放最短路径优先(OSPF)同样。最高的IP地址分配到回环接口选择作为路由器ID。如果没有配置的任何环回地址,最高的IP地址分配到其他接口选择作为路由器ID。

先决条件

要求

本文档没有任何特定的要求。

使用的组件

使用Cisco IOS�软件版本12.2(10b),此配置开发并且测试了。

本文档中的信息都是基于特定实验室环境中的设备创建的。本文档中使用的所有设备最初均采用原始(默认)配置。如果您是在真实网络上操作,请确保您在使用任何命令前已经了解其潜在影响。

规则

有关文档规则的详细信息,请参阅 Cisco 技术提示规则

问题

用被重新分配的路由遇到由于路由器在线状态有重复的EIGRP路由器ID的问题可以在此网络设置帮助下了解。

网络图

eigrp dupid.jpg

配置

Router4
interface Loopback0

 ip address 1.1.1.1 255.255.255.255

!

interface Loopback1

 ip address 10.10.10.10 255.255.255.0

!

interface Ethernet0

 ip address 172.16.3.4 255.255.255.0

!

router rip

 version 2

 network 10.0.0.0

 network 172.16.0.0

路由器 3
interface Loopback0

 ip address 2.2.2.2 255.255.255.255

!

interface Ethernet0

 ip address 172.16.3.3 255.255.255.0

 ip pim sparse-dense-mode

!

interface Serial1

 ip address 172.16.13.3 255.255.255.0

 clockrate 4000000

!

router eigrp 7

 redistribute rip metric 1 1 1 1 1

 network 172.16.0.0

!

router rip

 version 2

 network 172.16.0.0

路由器 1
interface Loopback0

 ip address 2.2.2.2 255.255.255.0

!

interface Serial1

 ip address 172.16.13.1 255.255.255.0

 no ip mroute-cache

!

router eigrp 7

 network 172.16.0.0

 auto-summary

 no eigrp log-neighbor-changes

显示命令

如以前显示, Router3再分布路由信息协议(RIP)路由到EIGRP。这是3路由表和EIGRP拓扑表。

Router-3#show ip route
Codes: C - connected, S - static, I - IGRP, 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, E - EGP
i - IS-IS, 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

     2.0.0.0/32 is subnetted, 1 subnets
C       2.2.2.2 is directly connected, Loopback0
R    10.0.0.0/8 [120/1] via 172.16.3.4, 00:00:25, Ethernet0 
!--- Router 3 sees network 10.0.0.0.

     172.16.0.0/24 is subnetted, 3 2 subnets
C       172.16.13.0 is directly connected, Serial1
C       172.16.3.0 is directly connected, Ethernet0
router-3#


router-3#show ip eigrp topology 10.0.0.0 255.0.0.0
IP-EIGRP (AS 7): topology entry for 10.0.0.0/8
  State is Passive, Query origin flag is 1, 1 Successor(s), FD is 2560000256
  Routing Descriptor Blocks:
  0.0.0.0, from Redistributed, Send flag is 0x0
      Composite metric is (2560000256/0), Route is External
      Vector metric:
        Minimum bandwidth is 1 Kbit
        Total delay is 10 microseconds
        Reliability is 1/255
        Load is 1/255
        Minimum MTU is 1
        Hop count is 0
      External data:
        Originating router is 2.2.2.2 (this system)
!--- Shows that Router 3 is the originating router of the external route.

        AS number of route is 0
        External protocol is RIP, external metric is 1
        Administrator tag is 0 (0x00000000)
router-3#

从上一个输出,您能看到Router3了解关于网络10.0.0.0通过RIP。通过再分配,路由被输入了到EIGRP拓扑表作为外部路由。Router3也显示它是外部路由的始发路由器;其EIGRP路由器ID是2.2.2.2。

因为Router3似乎再分布外部路由,在路由器1路由表里预计发现它。这是路由表和EIGRP拓扑表的显示路由器的1。

router-1#show ip route
Codes: C - connected, S - static, I - IGRP, 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, E - EGP
       i - IS-IS, 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

     2.0.0.0/24 is subnetted, 1 subnets
C       2.2.2.0 is directly connected, Loopback0
     172.16.0.0/24 is subnetted, 3 2 subnets
C       172.16.13.0 is directly connected, Serial1
D       172.16.3.0 [90/2195456] via 172.16.13.3, 00:31:59, Serial1
router-1#


router-1# show ip eigrp topology
IP-EIGRP Topology Table for AS(7)/ID(2.2.2.2)

Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
       r - reply Status, s - sia Status

P 172.16.13.0/24, 1 successors, FD is 2169856
         via Connected, Serial1
P 172.16.3.0/24, 1 successors, FD is 2195456
         via 172.16.13.3 (2195456/281600), Serial1
router-1#

从上一个输出您能看到预计路由10.0.0.0/8不在路由表或EIGRP拓扑表路由器里1。此的可能的原因是路由器1和3有同一个EIGRP路由器ID。在Cisco IOS软件版本12.0(2)及以上版本, Cisco记录在EIGRP事件日志的相同的路由器ID,您能用show ip eigrp events命令查看。这是此的输出路由器的1 :

router-1 #show ip eigrp events 
Event information for AS 7:
1    18:06:15.863 Change queue emptied, entries: 1
2    18:06:15.863 Ignored route, metric: 10.0.0.0 2560512256
3    18:06:15.863 Ignored route, neighbor info: 172.16.13.3 Serial2
4    18:06:15.863 Ignored route, dup router: 2.2.2.2


!--- Output suppressed.

从上一个输出您能看到相同的路由器ID是原因路由器1不接受从Router3的路由。

解决方案

解决方案将更改在其中一的路由器ID路由器通过更改在回环接口的最高的IP地址。如果ause Cisco IOS软件版本12.1(6)或以后,您能也使用eigrp router-id <router-id> router子命令为了更改路由器ID。在本例中,我们更改在路由器1.的路由器ID。

router-1(config)#router eigrp 7 
router-1(config-router)#eigrp router-id 3.3.3.3

注意: 问题清楚ip eigrp <自治系统命令,在您更改EIGRP路由器ID后。

外部路由在路由表里当前出现如显示此处。

router-1#show ip route
Codes: C - connected, S - static, I - IGRP, 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, E - EGP
       i - IS-IS, 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
     2.0.0.0/24 is subnetted, 1 subnets
C       2.2.2.0 is directly connected, Loopback0
     172.16.0.0/24 is subnetted, 2 subnets
C       172.16.13.0 is directly connected, Serial1
D       172.16.3.0 [90/2195456] via 172.16.13.3, 00:00:00, Serial1
D EX 10.0.0.0/8 [170/2560512256] via 172.16.13.3, 00:00:00, Serial1
router-1# 

相关信息


Document ID: 18685