说明

Monitor Link是Smart Link的补充，Smart Link无法感知上游设备的链路状态。Smart Link作为Monitor Link的上行链路，Monitor Link监控上行链路，上行链路出现故障，Moniot Link会把下行接口强制Down。

拓扑图

SW2的 G0/0/2 和G0/0/4 组成Smart link, 然后这个Smart Link和G0/0/1一起组成Monitor Link。

SW3 的G0/0/1 和 G0/0/2 组成Monitor Link。

配置Monitor Link

配置VLAN和Trunk

SW1，SW2，SW3，位置4个VLAN，VLAN 10，20，30，40

 

3台机器都如下配置

[SW1]vlan batch 10 20 30 40

[SW1]interface g0/0/1

[SW1-GigabitEthernet0/0/1]port link-type trunk

[SW1-GigabitEthernet0/0/1]port trunk allow-pass vlan 10 20 30 40

[SW1-GigabitEthernet0/0/1]int g0/0/2

[SW1-GigabitEthernet0/0/2]port link-type trunk

[SW1-GigabitEthernet0/0/2]port trunk allow-pass vlan 10 20 30 40

 

[SW2]vlan batch 10 20 30 40

[SW2]interface g0/0/1

[SW2-GigabitEthernet0/0/1]port link-type trunk

[SW2-GigabitEthernet0/0/1]port trunk allow-pass vlan 10 20 30 40

[SW2-GigabitEthernet0/0/1]interface g0/0/2

[SW2-GigabitEthernet0/0/2]port link-type trunk

[SW2-GigabitEthernet0/0/2]port trunk allow-pass vlan 10 20 30 40

[SW2-GigabitEthernet0/0/2]interface g0/0/3

[SW2-GigabitEthernet0/0/3]port link-type trunk

[SW2-GigabitEthernet0/0/3]port trunk allow-pass vlan 10 20 30 40

[SW2-GigabitEthernet0/0/3]interface g0/0/4

[SW2-GigabitEthernet0/0/4]port link-type trunk

[SW2-GigabitEthernet0/0/4]port trunk allow-pass vlan 10 20 30 40

 

[SW3]interface g0/0/1

[SW3-GigabitEthernet0/0/1]port link-type trunk

[SW3-GigabitEthernet0/0/1]port trunk allow-pass vlan 10 20 30 40

[SW3-GigabitEthernet0/0/1]interface g0/0/2

[SW3-GigabitEthernet0/0/2]port link-type trunk

[SW3-GigabitEthernet0/0/2]port trunk allow-pass vlan 10 20 30 40

[SW3-GigabitEthernet0/0/2]interface g0/0/3

[SW3-GigabitEthernet0/0/3]port link-type trunk

[SW3-GigabitEthernet0/0/3]port trunk allow-pass vlan 10 20 30 40

SW1和SW2创建Smart Link组

[SW1]smart-link group 1

[SW2]smart-link group 1

把接口成员加入Smart Link组

[SW1]int GigabitEthernet 0/0/1

[SW1-GigabitEthernet0/0/1]stp disable

[SW1-GigabitEthernet0/0/1]q

[SW1]int GigabitEthernet 0/0/2

[SW1-GigabitEthernet0/0/2]stp disable

[SW1]smart-link group 1

[SW1-smlk-group1]port GigabitEthernet 0/0/1 master         //设置主接口

[SW1-smlk-group1]port GigabitEthernet 0/0/2 slave        //设置从接口

 

[SW2]int GigabitEthernet 0/0/2

[SW2-GigabitEthernet0/0/2]stp disable

[SW2]int GigabitEthernet 0/0/4

[SW2-GigabitEthernet0/0/4]stp disable

[SW2]smart-link group 1

[SW2-smlk-group1]port GigabitEthernet 0/0/2 master

[SW2-smlk-group1]port GigabitEthernet 0/0/4 slave

 

查看下

配置Flush报文

在SW1 SW2 SW3上配置发送和接收Flush报文

[SW1]smart-link group 1

[SW1-smlk-group1]flush send control-vlan 10 password simple abc123        //发送密码abc123

 

[SW2]interface GigabitEthernet 0/0/1

[SW2-GigabitEthernet0/0/1]smart-link flush receive control-vlan 10 password simple abc123        //接收密码abc123

[SW2]int GigabitEthernet 0/0/3

[SW2-GigabitEthernet0/0/3]smart-link flush receive control-vlan 10 password simple abc123

 

[SW3]int GigabitEthernet 0/0/2

[SW3-GigabitEthernet0/0/2]smart-link flush receive control-vlan 10 password simple abc123

[SW3]int GigabitEthernet 0/0/3

[SW3-GigabitEthernet0/0/3]smart-link flush receive control-vlan 10 password simple abc123

 

设置回切功能和时间

[SW1]smart-link group 1

[SW1-smlk-group1]restore enable         //开启回切

[SW1-smlk-group1]timer wtr 30            //回切时间30s

 

[SW2]smart-link group 1

[SW2-smlk-group1]restore enable

[SW2-smlk-group1]timer wtr 30

 

开启Smart Link

S1和S2开启

[SW1]smart-link group 1

[SW1-smlk-group1]smart-link enable

 

[SW2]smart-link group 1

[SW2-smlk-group1]smart-link enable

 

创建Monitor Link组

在S2和S3创建

[SW2]monitor-link group 1

[SW3]monitor-link group 1

查看命令 dis monitor-link group 1

加入上行和下行链路

在S2和S3配置

[SW2]monitor-link group 1

[SW2-mtlk-group1]smart-link group 1 uplink         //上行链路SMLK1 必须up

[SW2-mtlk-group1]port GigabitEthernet 0/0/1 downlink         //如果Smart link down了，强制G0/0/1 接口down

 

[SW3]monitor-link group 1

[SW3-mtlk-group1]port GigabitEthernet 0/0/1 uplink

[SW3-mtlk-group1]port GigabitEthernet 0/0/2 downlink

设置回切Monitor和回切时间为4s

在S2和S3配置

[SW2]monitor-link group 1

[SW2-mtlk-group1]timer recover-time 4        //默认时间是3s

 

[SW3]monitor-link group 1

[SW3-mtlk-group1]timer recover-time 4

 

 

故障演习

模拟S3故障

把S3的G0/0/1 接口Down掉

[SW3]int GigabitEthernet 0/0/1

[SW3-GigabitEthernet0/0/1]shutdown

看到G0/0/2 被强制接口Down了

在开启G0/0/1接口

[SW3]int GigabitEthernet 0/0/1

[SW3-GigabitEthernet0/0/1]undo shutdown

切换成功。

模拟S2故障

把S2的G0/0/2接口Down

[SW2]int GigabitEthernet 0/0/2

[SW2-GigabitEthernet0/0/2]shutdown

我们先查看Smart Link，发现已经切换了

在查看Monitor Link

没切换，因为Smart Link组中只断了一个，所以整个Smart Link组没有断

把S2的G0/0/4接口也Down了

[SW2]int GigabitEthernet 0/0/4

[SW2-GigabitEthernet0/0/4]shutdown

 

现在Down了

我们在去查看SW1的Smart Link发现也切换了。

 

我们把S2的接口都up

[SW2]int GigabitEthernet 0/0/4

[SW2-GigabitEthernet0/0/4]undo shutdown

[SW2]int GigabitEthernet 0/0/2

[SW2-GigabitEthernet0/0/2]undo shutdown

Monitor Link恢复了

SW1也ok了

实验完成