EIGRP路由问题

Question

我对EIGRP有个问题。但是首先，下面是拓扑结构：

我做过EIGRP路由，但这有点奇怪。PC0 -> PC1可以ping，PC3 -> PC2可以ping。但是，我不能平PC0 -> PC2，PC0 -> PC3。这也发生在PC1上。以下是我所有的路由器配置：

-ROUTER0 0-

interface FastEthernet0/0
 ip address 10.10.0.1 255.255.255.252
 duplex auto
 speed auto
!
interface FastEthernet0/0.20
 encapsulation dot1Q 20
 ip address 10.10.3.1 255.255.255.252
!
interface FastEthernet0/1
 ip address 192.168.1.254 255.255.255.0
 duplex auto
 speed auto
!
interface Vlan1
 no ip address
 shutdown
!
router eigrp 10
 network 10.0.0.0
 network 192.168.0.0
 network 192.168.1.0
 network 192.168.2.0
 network 192.168.3.0
 network 192.168.4.0
 auto-summary
!
ip classless
ip route 192.168.0.0 255.255.255.0 FastEthernet0/1 
!
ip flow-export version 9
!
!
!
!
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
 login
!
!
!
end

-ROUTER1 1-

interface FastEthernet0/0
 ip address 10.10.0.2 255.255.255.252
 duplex auto
 speed auto
!
interface FastEthernet0/0.30
 encapsulation dot1Q 30
 ip address 10.10.1.1 255.255.255.252
!
interface FastEthernet0/1
 ip address 192.168.2.254 255.255.255.0
 duplex auto
 speed auto
!
interface Vlan1
 no ip address
 shutdown
!
router eigrp 10
 network 10.0.0.0
 network 192.168.0.0
 network 192.168.1.0
 network 192.168.2.0
 network 192.168.3.0
 network 192.168.4.0
 auto-summary
!
ip classless
ip route 192.168.0.0 255.255.255.0 FastEthernet0/1 
!
ip flow-export version 9
!
!
!
!
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
 login
!
!
!
end

-ROUTER2 2-

interface FastEthernet0/0
 ip address 10.10.2.1 255.255.255.252
 duplex auto
 speed auto
!
interface FastEthernet0/0.30
 encapsulation dot1Q 30
 ip address 10.10.1.2 255.255.255.252
!
interface FastEthernet0/1
 ip address 192.168.3.254 255.255.255.0
 duplex auto
 speed auto
!
interface Vlan1
 no ip address
 shutdown
!
router eigrp 1
 auto-summary
!
router eigrp 10
 network 10.0.0.0
 network 192.168.0.0
 network 192.168.1.0
 network 192.168.2.0
 network 192.168.3.0
 network 192.168.4.0
 auto-summary
!
ip classless
ip route 192.168.0.0 255.255.255.0 FastEthernet0/1 
!
ip flow-export version 9
!
!
!
!
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
 login
!
!
!
end

-ROUTER3 3-

interface FastEthernet0/0
 ip address 10.10.2.2 255.255.255.252
 duplex auto
 speed auto
!
interface FastEthernet0/0.20
 encapsulation dot1Q 20
 ip address 10.10.3.2 255.255.255.252
!
interface FastEthernet0/1
 ip address 192.168.4.254 255.255.255.0
 duplex auto
 speed auto
!
interface Vlan1
 no ip address
 shutdown
!
router eigrp 10
 network 10.0.0.0
 network 192.168.0.0
 network 192.168.1.0
 network 192.168.2.0
 network 192.168.3.0
 network 192.168.4.0
 auto-summary
!
ip classless
ip route 192.168.0.0 255.255.255.0 FastEthernet0/1 
!
ip flow-export version 9
!
!
!
!
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
 login
!
!
!
end

看来路线到了。但有人知道为什么会这样吗？谢谢。

Answer 1

我已经创建了与图像显示的相同的拓扑结构，并将您的信任放入路由器，并且我能够从PC0中选择所有的PC。所有PC都有与路由器Fa0/1接口相同的/24网络中的IP地址，并且都将默认网关设置为路由器的IP (192.168.x.254)。

猫3560的配置：

interface FastEthernet0/1
 switchport trunk allowed vlan 1,20
 switchport trunk encapsulation dot1q
 switchport mode trunk
!
interface FastEthernet0/2
 switchport trunk allowed vlan 1,30
 switchport trunk encapsulation dot1q
 switchport mode trunk
!
interface FastEthernet0/3
 switchport trunk allowed vlan 1,30
 switchport trunk encapsulation dot1q
 switchport mode trunk
!
interface FastEthernet0/4
 switchport trunk allowed vlan 1,20
 switchport trunk encapsulation dot1q
 switchport mode trunk
!

此外，我还在交换机上创建了VLAN：

Switch(config)# vlan 20
Switch(config)# vlan 30

平评结果：

C:\>ping 192.168.2.1

Pinging 192.168.2.1 with 32 bytes of data:

Request timed out.
Reply from 192.168.2.1: bytes=32 time<1ms TTL=126
Reply from 192.168.2.1: bytes=32 time<1ms TTL=126

Ping statistics for 192.168.2.1:
    Packets: Sent = 3, Received = 2, Lost = 1 (34% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms

Control-C
^C
C:\>ping 192.168.3.1

Pinging 192.168.3.1 with 32 bytes of data:

Request timed out.
Reply from 192.168.3.1: bytes=32 time<1ms TTL=125
Reply from 192.168.3.1: bytes=32 time<1ms TTL=125

Ping statistics for 192.168.3.1:
    Packets: Sent = 3, Received = 2, Lost = 1 (34% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms

Control-C
^C
C:\>ping 192.168.4.1

Pinging 192.168.4.1 with 32 bytes of data:

Request timed out.
Reply from 192.168.4.1: bytes=32 time<1ms TTL=126
Reply from 192.168.4.1: bytes=32 time=1ms TTL=126

Ping statistics for 192.168.4.1:
    Packets: Sent = 3, Received = 2, Lost = 1 (34% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 1ms, Average = 0ms

Control-C
^C

Answer 2

在再次查看网络图并考虑了OP获得的提示(“子接口”)之后，我想我现在看到了它的意义所在。

这一答案假定：

• Cat3560将不参与路由。
• Cat3560只是有一组VLANs，每个都可以模拟从一个路由器到另一个路由器的点点链路，几乎就像它们之间有一个直接的电缆一样。
• 10.10.x.0/30子网用于这些点对点链接。

有一个替代的设置，也解决了挑战，但需要L3切换(可能是EIGRP，为了好玩)也运行在Cat3560上。我更喜欢这种选择，但挑战似乎是双重的:在Cat3560上使用VLAN进行L2交换，以及(动态)路由器上带有子接口的路由，因此我们将为此而努力。

这将需要交换机上的一些VLAN：

vlan 10
 name R0-to-R1

vlan 20
 name R0-to-R3

vlan 30
 name R3-to-R2

vlan 40
 name R2-to-R1

并将VLAN选择性地映射到路由器连接到的4个交换机端口：

int f0/1
 description Router0 fa0/0
 switchport trunk encapsulation dot1q
 switchport mode trunk
 switchport trunk allowed vlan 10,20
 spanning-tree portfast trunk

int f0/2
 description Router1 fa0/0
 switchport trunk encapsulation dot1q
 switchport mode trunk
 switchport trunk allowed vlan 10,40
 spanning-tree portfast trunk

int f0/3
 description Router2 fa0/0
 switchport trunk encapsulation dot1q
 switchport mode trunk
 switchport trunk allowed vlan 30,40
 spanning-tree portfast trunk

int f0/4
 description Router3 fa0/0
 switchport trunk encapsulation dot1q
 switchport mode trunk
 switchport trunk allowed vlan 20,30
 spanning-tree portfast trunk

请注意:从技术上讲，没有必要在交换机端口上设置switchport trunk allowed vlan...。创建VLAN并将端口设置为mode trunk就足够了。在维护良好的环境中，在给定的开关端口上定义哪个(一组) VLAN(s)是可接受的，这是很好的实践。

然后，在每个路由器上，你需要

• 局域网接口192.168.x.0/24。我将为路由器选择.1。有些人更喜欢子网(.254)中的最后一个地址--这只是一个特定环境的品味、指导方针和操作实践的问题。
• WAN端的两个子接口，由VLAN标记分隔
• 一个不错的EIGRP设置，请参阅命令片段中的注释。

我将给出一个路由器的示例--其他路由器将留给读者作为练习。

!=========
!ROUTER 0
!========

int f0/0
 description Switch0 fast0/1

int f0/0.10
 description Router1 fast0/0.10 (via VLAN 10)
 enapsulation dot1q 10
 ip adress 10.10.0.1 255.255.255.252

int f0/0.20
 description Router3 fast0/0.20 (via VLAN 20)
 encapsulation dot1q 20
 ip adress 10.10.3.1 255.255.255.252

int fa0/1
 description LAN to PC0
 ip address 192.168.1.1 255.255.255.0


router eigrp 1
!
! Summarization is for large networks with multiple hierarchies and
! tiers of routing. 
! It just creates obstacles for a novice. Leave it off. (almost) always.
!
 no auto-summary 
!
! for the sake of clarity, add the to-be-EIGRP-activated 
! interfaces with the host wildcard mask. 
! in EIGRP, the network statements just define a filter list of IP adresses. 
! Interfaces on the router that have an address matching the 
! filter will be enanbled for EIGRP.
!   
 network 192.168.1.1 0.0.0.0
 network 10.10.0.1 0.0.0.0
 network 10.10.3.1 0.0.0.0
!
!
! good practice (optional): Don't be looking for EIGRP neighbors 
! in "client subnets", where there won't be any. 
! Make all interfaces passive, then explicitely enable 
! the (sub)interfaces that will actually have to speak EIGRP 
! to potential neighbors.
!
! YES, it is actually correct and valid to have the LAN 
! side enabled for EIGRP, but then leave it passive.

 passive-interface default
 no passive-interface fast0/0.10
 no passive-interface fast0/0.20