我已经创建了与图像上显示的相同的拓扑，并将您的配置放入路由器，我能够从 PC0 ping 所有 PC。所有 PC 的 IP 地址都在与路由器 Fa0/1 接口相同的 /24 网络中，并且都将默认网关设置为路由器的 IP (192.168.x.254)。

Cat 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
!

我还在交换机上创建了 VLAN：

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

平结果：

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

在再次查看网络图并考虑 OP 得到的提示（“子接口”）之后，我想我现在明白了这意味着什么。

这个答案假设：

• Cat3560 将不参与路由
• Cat3560 只有一组 VLAN，每个 VLAN 都充当从一个路由器到另一个路由器的点对点链路的仿真，几乎就像它们之间有直接的电缆一样好。
• 10.10.x.0/30 子网用于这些点对点链路。

有一个替代设置也可以解决这个挑战，但需要 L3 交换（可能是 EIGRP，为了它的乐趣）也可以在 Cat3560 上运行。我更喜欢这种替代方案，但挑战似乎是双重的：在 Cat3560 上使用 VLAN 进行 L2 交换，以及在路由器上使用子接口进行（动态）路由，因此我们将朝着这个方向努力。

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

以及将 VLAN 选择性映射到路由器所连接的 4 个交换端口：

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switchport trunk allowed vlan...在交换机端口上有。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，最好定义给定交换机端口上可接受的 VLAN（组）。

然后，在每个路由器上，您需要

• LAN 接口 192.168.x.0/24。我将为路由器选择 .1。有些人更喜欢子网中的最后一个地址 (.254) - 这只是给定环境的品味、指南和操作实践的问题。
• WAN侧两个子接口，用VLAN标签隔开
• 一个不错的 EIGRP 设置，请参阅命令片段中的注释。

我将举一个路由器的例子——其他的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