0x0 拓扑图

  • 要求
    1. 所有交换机属于一个MST域
    2. 所有交换机的实例1包含vlan10、vlan20;实例2包含vlan30、vlan40
    3. LSW1的为实例1的主根，LSW2为实例2的主根
    4. LSW1和LSW2运行VRRP协议
    5. LSW1为vlan 10 20 30的MASTER，LSW2为vlan40的MASTER
    6. 所有PC机可以互通

0x1 指令配置

  • LSW1 
    undo info-center enable
vlan batch 10 20 30 40
stp instance 1 priority 4096
stp instance 2 priority 8192 //更改实例对应的优先级
stp region-configuration //设置MSTP区域
 region-name RA
 revision-level 1
 instance 1 vlan 10 20
 instance 2 vlan 30 40
 active region-configuration
interface Vlanif10 //设置SVI10 维护的虚拟IP
 ip address 192.168.10.252 255.255.255.0
 vrrp vrid 10 virtual-ip 192.168.10.254
 vrrp vrid 10 priority 110
interface Vlanif20
 ip address 192.168.20.252 255.255.255.0
 vrrp vrid 20 virtual-ip 192.168.20.254
 vrrp vrid 20 priority 110
interface Vlanif30
 ip address 192.168.30.252 255.255.255.0
 vrrp vrid 30 virtual-ip 192.168.30.254
 vrrp vrid 30 priority 110
interface Vlanif40
 ip address 192.168.40.252 255.255.255.0
 vrrp vrid 40 virtual-ip 192.168.40.254
interface GigabitEthernet0/0/1
 port link-type access
 port default vlan 40
interface GigabitEthernet0/0/2
 port link-type trunk
 port trunk allow-pass vlan 2 to 4094
interface GigabitEthernet0/0/3
 port link-type trunk
 port trunk allow-pass vlan 2 to 4094
  • LSW2 
    undo info-center enable
vlan batch 10 20 30 40
stp instance 1 priority 8192
stp instance 2 priority 4096 //更改实例对应的优先级
stp region-configuration //设置MSTP区域
 region-name RA
 revision-level 1
 instance 1 vlan 10 20
 instance 2 vlan 30 40
 active region-configuration
interface Vlanif10 //设置SVI10 维护的虚拟IP
 ip address 192.168.10.252 255.255.255.0
 vrrp vrid 10 virtual-ip 192.168.10.254
interface Vlanif20
 ip address 192.168.20.252 255.255.255.0
 vrrp vrid 20 virtual-ip 192.168.20.254
interface Vlanif30
 ip address 192.168.30.252 255.255.255.0
 vrrp vrid 30 virtual-ip 192.168.30.254
interface Vlanif40 //设置SVI40 维护的IP和优先级
 ip address 192.168.40.252 255.255.255.0
 vrrp vrid 40 virtual-ip 192.168.40.254
 vrrp vrid 40 priority 110
interface GigabitEthernet0/0/1
 port link-type access
 port default vlan 30
interface GigabitEthernet0/0/2
 port link-type trunk
 port trunk allow-pass vlan 2 to 4094
interface GigabitEthernet0/0/3
 port link-type trunk
 port trunk allow-pass vlan 2 to 4094
  • LSW3 
    undo info-center enable
vlan batch 10 20 30 40
stp region-configuration //设置MSTP区域
 region-name RA
 revision-level 1
 instance 1 vlan 10 20
 instance 2 vlan 30 40
 active region-configuration
interface GigabitEthernet0/0/1 //设置接口模式
 port link-type trunk
 port trunk allow-pass vlan 2 to 4094
interface GigabitEthernet0/0/2
 port link-type trunk
 port trunk allow-pass vlan 2 to 4094
interface GigabitEthernet0/0/3
 port link-type access
 port default vlan 10
interface GigabitEthernet0/0/4
 port link-type access
 port default vlan 20
interface GigabitEthernet0/0/5
 port link-type access
 port default vlan 40

0x2 连通性验证

  • MSTI1主根验证

  • MSTI2主根验证

  • LSW1为vlan 10 vlan 20 vlan 30的MSATER

  • LSW2为vlan 40的MASTER

  • PC1(vlan40) -> PC7(VLAN40),因为vlan40属于实例2,对于LSW3的实例2应该阻塞g0/0/1,再g0/0/2口抓包

  • PC1(vlan40) -> PC3(VLAN10),因为vlan40属于实例2,对于LSW3的实例2应该阻塞g0/0/1,再g0/0/2口抓包

因为三层交换机使用的是SVI接口，在入接口打上对应的PVID后，转发的时候会查看是二层转发还是三层转发，三层转发就要查路由表，并且把vlan id改变成转发目的对应的vlan id(svi的交换层次把id去掉，交给接收方的网关，网关再转发，转发的时候打上接收方的id)，所以在交换机内部数据包的Vlan id被改为10 所以会走左边进行转发

  • PC1(vlan40) -> PC3(VLAN10),因为vlan40属于实例2,对于LSW3的实例2应该阻塞g0/0/1,再g0/0/2口抓包

  • VRRP备份验证
  • PC1(vlan40) -> PC7(VLAN40)
  • 删除这条线后
  • PC1(vlan40) -> PC7(VLAN40)
  • PC1(vlan40) -> PC7(VLAN40) 走备份链路