在 GNS3 中，我尝试使用 EIGRP 在环形拓扑中配置五个 Cisco 3660 路由器，作为尝试学习如何使用 EIGRP 的早期练习：
这些路由器和虚拟 PC 根据下表进行配置。所有网络都是/24：
除了 IP，每个路由器接口都有以下选项：
no shut
bandwidth 1000
每个路由器还输入了以下 EIGRP 配置：
router eigrp 1
network <network of e1/0, ending in .0>
network <network of e1/1, ending in .0>
network <network of f0/0, ending in .0>
no auto-summary
没有从默认值修改其他配置选项。路由器运行软件 C3660-IK9O3S-M 12.4(13b)
目前我观察到任何（跟踪）路由都不会使用 R5 和 R1 之间的链接（例如，来自 PC5 -> PC1 的路由通过 R5 -> R4 -> R3 -> R2 -> R1 而不是 R5 -> R1） . 此外，删除此路径上的任何链接（例如 R3 和 R4 之间的链接）将导致 R5 在从 PC5 ping PC1 时报告目标主机不可达。我已确认所有路由器上的所有接口都具有正确的 IP 并且已启动。
我希望在当前的配置中，在所有带宽相等的情况下，路由将选择跳数最少的路径，并且如果两个相邻路由器之间的链路发生故障，流量将在环中以相反的方式流动。
进一步调查表明，R5 不知道其 E1/0 接口上的任何路由，除了直接连接的 192.168.5.0/24 网络：
R5#sho ip eigrp top all
IP-EIGRP Topology Table for AS(1)/ID(192.168.50.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - reply Status, s - sia Status
P 192.168.40.0/24, 1 successors, FD is 2588160, serno 5
via 192.168.4.1 (2588160/2562560), Ethernet1/0
P 192.168.50.0/24, 1 successors, FD is 2562560, serno 3
via Connected, FastEthernet0/0
P 192.168.10.0/24, 1 successors, FD is 2664960, serno 30
via 192.168.4.1 (2664960/2639360), Ethernet1/0
P 192.168.1.0/24, 1 successors, FD is 2662400, serno 28
via 192.168.4.1 (2662400/2636800), Ethernet1/0
P 192.168.2.0/24, 1 successors, FD is 2636800, serno 26
via 192.168.4.1 (2636800/2611200), Ethernet1/0
P 192.168.3.0/24, 1 successors, FD is 2611200, serno 4
via 192.168.4.1 (2611200/2585600), Ethernet1/0
P 192.168.4.0/24, 1 successors, FD is 2585600, serno 1
via Connected, Ethernet1/0
P 192.168.5.0/24, 1 successors, FD is 2585600, serno 2
via Connected, Ethernet1/1
P 192.168.30.0/24, 1 successors, FD is 2613760, serno 27
via 192.168.4.1 (2613760/2588160), Ethernet1/0
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - reply Status, s - sia Status
P 192.168.20.0/24, 1 successors, FD is 2639360, serno 29
via 192.168.4.1 (2639360/2613760), Ethernet1/0
R5#sho ip rou
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
D 192.168.30.0/24 [90/2613760] via 192.168.4.1, 00:49:53, Ethernet1/0
D 192.168.10.0/24 [90/2664960] via 192.168.4.1, 00:49:53, Ethernet1/0
D 192.168.40.0/24 [90/2588160] via 192.168.4.1, 01:01:11, Ethernet1/0
C 192.168.4.0/24 is directly connected, Ethernet1/0
D 192.168.20.0/24 [90/2639360] via 192.168.4.1, 00:49:53, Ethernet1/0
C 192.168.5.0/24 is directly connected, Ethernet1/1
C 192.168.50.0/24 is directly connected, FastEthernet0/0
D 192.168.1.0/24 [90/2662400] via 192.168.4.1, 00:49:56, Ethernet1/0
D 192.168.2.0/24 [90/2636800] via 192.168.4.1, 00:49:56, Ethernet1/0
D 192.168.3.0/24 [90/2611200] via 192.168.4.1, 01:01:14, Ethernet1/0
我对这种 EIGRP 配置的期望是否可行？如果不是，为什么不呢？我应该看什么技术/技术？如果是这样，可能出了什么问题，我可以采取哪些步骤来有效地解决这个问题？
到目前为止的参考资料：
- https://petri.com/how-to-configure-eigrp-on-your-cisco-router
- https://hub.packtpub.com/implementing-the-eigrp-routing-protocol-tutorial/
- 如何为空间分集 T1 提供故障转移
更新：作为我实验的一部分，我更新了路由器拓扑。这是与以下配置文件一起使用的新拓扑：
路由器配置（包括从 R2/e1/2 到 R4/e1/2 的附加链路以及相关的 EIGRP 配置）：
R1：
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R1
!
no aaa new-model
memory-size iomem 5
no ip icmp rate-limit unreachable
!
ip cef
no ip domain lookup
!
ip tcp synwait-time 5
!
interface FastEthernet0/0
bandwidth 1000
ip address 192.168.10.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Ethernet1/0
bandwidth 1000
ip address 192.168.5.2 255.255.255.0
half-duplex
!
interface Ethernet1/1
bandwidth 1000
ip address 192.168.1.1 255.255.255.0
half-duplex
!
interface Ethernet1/2
no ip address
shutdown
half-duplex
!
interface Ethernet1/3
no ip address
shutdown
half-duplex
!
router eigrp 1
network 192.168.1.0
network 192.168.2.0
network 192.168.10.0
no auto-summary
!
no ip http server
no ip http secure-server
!
no cdp log mismatch duplex
!
control-plane
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
line vty 0 4
login
!
end
R2：
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R2
!
boot-start-marker
boot-end-marker
!
no aaa new-model
memory-size iomem 5
no ip icmp rate-limit unreachable
!
ip cef
no ip domain lookup
!
ip tcp synwait-time 5
!
interface FastEthernet0/0
bandwidth 1000
ip address 192.168.20.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Ethernet1/0
bandwidth 1000
ip address 192.168.1.2 255.255.255.0
half-duplex
!
interface Ethernet1/1
bandwidth 1000
ip address 192.168.2.1 255.255.255.0
half-duplex
!
interface Ethernet1/2
bandwidth 1000
ip address 192.168.100.1 255.255.255.0
half-duplex
!
interface Ethernet1/3
no ip address
shutdown
half-duplex
!
router eigrp 1
network 192.168.1.0
network 192.168.2.0
network 192.168.20.0
network 192.168.100.0
no auto-summary
!
no ip http server
no ip http secure-server
!
no cdp log mismatch duplex
!
!
control-plane
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
line vty 0 4
login
!
end
R3：
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R3
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
memory-size iomem 5
no ip icmp rate-limit unreachable
!
!
ip cef
no ip domain lookup
!
ip tcp synwait-time 5
!
interface FastEthernet0/0
bandwidth 1000
ip address 192.168.30.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Ethernet1/0
bandwidth 1000
ip address 192.168.2.2 255.255.255.0
half-duplex
!
interface Ethernet1/1
bandwidth 1000
ip address 192.168.3.1 255.255.255.0
half-duplex
!
interface Ethernet1/2
no ip address
shutdown
half-duplex
!
interface Ethernet1/3
no ip address
shutdown
half-duplex
!
router eigrp 1
network 192.168.2.0
network 192.168.3.0
network 192.168.30.0
no auto-summary
!
no ip http server
no ip http secure-server
!
no cdp log mismatch duplex
!
control-plane
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
line vty 0 4
login
!
end
R4：
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R4
!
boot-start-marker
boot-end-marker
!
no aaa new-model
memory-size iomem 5
no ip icmp rate-limit unreachable
!
ip cef
no ip domain lookup
!
ip tcp synwait-time 5
!
interface FastEthernet0/0
bandwidth 1000
ip address 192.168.40.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Ethernet1/0
bandwidth 1000
ip address 192.168.3.2 255.255.255.0
half-duplex
!
interface Ethernet1/1
bandwidth 1000
ip address 192.168.4.1 255.255.255.0
half-duplex
!
interface Ethernet1/2
bandwidth 1000
ip address 192.168.100.2 255.255.255.0
half-duplex
!
interface Ethernet1/3
no ip address
shutdown
half-duplex
!
router eigrp 1
network 192.168.3.0
network 192.168.4.0
network 192.168.40.0
network 192.168.100.0
no auto-summary
!
no ip http server
no ip http secure-server
!
no cdp log mismatch duplex
!
control-plane
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
line vty 0 4
login
!
end
R5：
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R5
!
boot-start-marker
boot-end-marker
!
no aaa new-model
memory-size iomem 5
no ip icmp rate-limit unreachable
!
ip cef
no ip domain lookup
!
ip tcp synwait-time 5
!
interface FastEthernet0/0
bandwidth 1000
ip address 192.168.50.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Ethernet1/0
bandwidth 1000
ip address 192.168.4.2 255.255.255.0
half-duplex
!
interface Ethernet1/1
bandwidth 1000
ip address 192.168.5.1 255.255.255.0
half-duplex
!
interface Ethernet1/2
no ip address
shutdown
half-duplex
!
interface Ethernet1/3
no ip address
shutdown
half-duplex
!
router eigrp 1
network 192.168.4.0
network 192.168.5.0
network 192.168.50.0
no auto-summary
!
no ip http server
no ip http secure-server
!
no cdp log mismatch duplex
!
control-plane
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
line vty 0 4
login
!
end
R1 CDP 和 EIGRP 邻居：
R1#show cdp nei det
-------------------------
Device ID: R2
Entry address(es):
IP address: 192.168.1.2
Platform: Cisco 3660, Capabilities: Router Switch IGMP
Interface: Ethernet1/1, Port ID (outgoing port): Ethernet1/0
Holdtime : 146 sec
Version :
Cisco IOS Software, 3600 Software (C3660-IK9O3S-M), Version 12.4(13b), RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Tue 24-Apr-07 21:18 by prod_rel_team
advertisement version: 2
VTP Management Domain: ''
Duplex: half
-------------------------
Device ID: R5
Entry address(es):
IP address: 192.168.5.1
Platform: Cisco 3660, Capabilities: Router Switch IGMP
Interface: Ethernet1/0, Port ID (outgoing port): Ethernet1/1
Holdtime : 135 sec
Version :
Cisco IOS Software, 3600 Software (C3660-IK9O3S-M), Version 12.4(13b), RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Tue 24-Apr-07 21:18 by prod_rel_team
advertisement version: 2
VTP Management Domain: ''
Duplex: half
R1#sho ip eigrp neighbors detail
IP-EIGRP neighbors for process 1
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 192.168.1.2 Et1/1 14 02:08:10 58 783 0 42
Version 12.4/1.2, Retrans: 9, Retries: 0, Prefixes: 9
R1#sho ip eigrp neighbors
IP-EIGRP neighbors for process 1
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 192.168.1.2 Et1/1 11 02:08:18 58 783 0 42
R2 CDP 和 EIGRP 邻居：
R2# sho cdp nei det
-------------------------
Device ID: R3
Entry address(es):
IP address: 192.168.2.2
Platform: Cisco 3660, Capabilities: Router Switch IGMP
Interface: Ethernet1/1, Port ID (outgoing port): Ethernet1/0
Holdtime : 135 sec
Version :
Cisco IOS Software, 3600 Software (C3660-IK9O3S-M), Version 12.4(13b), RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Tue 24-Apr-07 21:18 by prod_rel_team
advertisement version: 2
VTP Management Domain: ''
Duplex: half
-------------------------
Device ID: R1
Entry address(es):
IP address: 192.168.1.1
Platform: Cisco 3660, Capabilities: Router Switch IGMP
Interface: Ethernet1/0, Port ID (outgoing port): Ethernet1/1
Holdtime : 119 sec
Version :
Cisco IOS Software, 3600 Software (C3660-IK9O3S-M), Version 12.4(13b), RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Tue 24-Apr-07 21:18 by prod_rel_team
advertisement version: 2
VTP Management Domain: ''
Duplex: half
-------------------------
Device ID: R4
Entry address(es):
IP address: 192.168.100.2
Platform: Cisco 3660, Capabilities: Router Switch IGMP
Interface: Ethernet1/2, Port ID (outgoing port): Ethernet1/2
Holdtime : 158 sec
Version :
Cisco IOS Software, 3600 Software (C3660-IK9O3S-M), Version 12.4(13b), RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Tue 24-Apr-07 21:18 by prod_rel_team
advertisement version: 2
VTP Management Domain: ''
Duplex: half
R2#sho ip eig nei det
IP-EIGRP neighbors for process 1
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
2 192.168.100.2 Et1/2 13 01:14:45 16 200 0 31
Version 12.4/1.2, Retrans: 1, Retries: 0, Prefixes: 6
1 192.168.1.1 Et1/0 13 02:10:28 26 200 0 14
Version 12.4/1.2, Retrans: 2, Retries: 0, Prefixes: 1
0 192.168.2.2 Et1/1 11 02:10:28 28 200 0 22
Version 12.4/1.2, Retrans: 2, Retries: 0, Prefixes: 6
R3 CDP 和 EIGRP 邻居：
R3# sho cdp nei det
-------------------------
Device ID: R2
Entry address(es):
IP address: 192.168.2.1
Platform: Cisco 3660, Capabilities: Router Switch IGMP
Interface: Ethernet1/0, Port ID (outgoing port): Ethernet1/1
Holdtime : 161 sec
Version :
Cisco IOS Software, 3600 Software (C3660-IK9O3S-M), Version 12.4(13b), RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Tue 24-Apr-07 21:18 by prod_rel_team
advertisement version: 2
VTP Management Domain: ''
Duplex: half
-------------------------
Device ID: R4
Entry address(es):
IP address: 192.168.3.2
Platform: Cisco 3660, Capabilities: Router Switch IGMP
Interface: Ethernet1/1, Port ID (outgoing port): Ethernet1/0
Holdtime : 0 sec
Version :
Cisco IOS Software, 3600 Software (C3660-IK9O3S-M), Version 12.4(13b), RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Tue 24-Apr-07 21:18 by prod_rel_team
advertisement version: 2
VTP Management Domain: ''
Duplex: half
R3#sho ip eig nei det
IP-EIGRP neighbors for process 1
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
1 192.168.3.2 Et1/1 10 01:25:21 374 2244 0 33
Version 12.4/1.2, Retrans: 0, Retries: 0, Prefixes: 8
0 192.168.2.1 Et1/0 13 02:09:05 74 444 0 41
Version 12.4/1.2, Retrans: 2, Retries: 0, Prefixes: 8
R4 CDP 和 EIGRP 邻居：
R4#sho cdp nei det
-------------------------
Device ID: R2
Entry address(es):
IP address: 192.168.100.1
Platform: Cisco 3660, Capabilities: Router Switch IGMP
Interface: Ethernet1/2, Port ID (outgoing port): Ethernet1/2
Holdtime : 137 sec
Version :
Cisco IOS Software, 3600 Software (C3660-IK9O3S-M), Version 12.4(13b), RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Tue 24-Apr-07 21:18 by prod_rel_team
advertisement version: 2
VTP Management Domain: ''
Duplex: half
-------------------------
Device ID: R3
Entry address(es):
IP address: 192.168.3.1
Platform: Cisco 3660, Capabilities: Router Switch IGMP
Interface: Ethernet1/0, Port ID (outgoing port): Ethernet1/1
Holdtime : 121 sec
Version :
Cisco IOS Software, 3600 Software (C3660-IK9O3S-M), Version 12.4(13b), RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Tue 24-Apr-07 21:18 by prod_rel_team
advertisement version: 2
VTP Management Domain: ''
Duplex: half
-------------------------
Device ID: R5
Entry address(es):
IP address: 192.168.4.2
Platform: Cisco 3660, Capabilities: Router Switch IGMP
Interface: Ethernet1/1, Port ID (outgoing port): Ethernet1/0
Holdtime : 149 sec
Version :
Cisco IOS Software, 3600 Software (C3660-IK9O3S-M), Version 12.4(13b), RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Tue 24-Apr-07 21:18 by prod_rel_team
advertisement version: 2
VTP Management Domain: ''
Duplex: half
R4#sho ip eig nei det
IP-EIGRP neighbors for process 1
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
2 192.168.100.1 Et1/2 10 01:16:06 1033 5000 0 43
Version 12.4/1.2, Retrans: 0, Retries: 0, Prefixes: 5
1 192.168.3.1 Et1/0 14 01:27:32 26 200 0 23
Version 12.4/1.2, Retrans: 1, Retries: 0, Prefixes: 5
0 192.168.4.2 Et1/1 12 02:10:36 24 200 0 12
Version 12.4/1.2, Retrans: 1, Retries: 0, Prefixes: 2
R5 CDP 和 EIGRP 邻居：
R5#sho cdp nei det
-------------------------
Device ID: R1
Entry address(es):
IP address: 192.168.5.2
Platform: Cisco 3660, Capabilities: Router Switch IGMP
Interface: Ethernet1/1, Port ID (outgoing port): Ethernet1/0
Holdtime : 120 sec
Version :
Cisco IOS Software, 3600 Software (C3660-IK9O3S-M), Version 12.4(13b), RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Tue 24-Apr-07 21:18 by prod_rel_team
advertisement version: 2
VTP Management Domain: ''
Duplex: half
-------------------------
Device ID: R4
Entry address(es):
IP address: 192.168.4.1
Platform: Cisco 3660, Capabilities: Router Switch IGMP
Interface: Ethernet1/0, Port ID (outgoing port): Ethernet1/1
Holdtime : 123 sec
Version :
Cisco IOS Software, 3600 Software (C3660-IK9O3S-M), Version 12.4(13b), RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Tue 24-Apr-07 21:18 by prod_rel_team
advertisement version: 2
VTP Management Domain: ''
Duplex: half
R5#sho ip eig nei det
IP-EIGRP neighbors for process 1
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 192.168.4.1 Et1/0 13 03:06:46 68 918 0 32
Version 12.4/1.2, Retrans: 5, Retries: 0, Prefixes: 8