7.4 替代方案

2.Monitor Link配置

1）SW2上行接口shutdown，SW1无法感知感知故障，主从不会切换。

[SW2-GigabitEthernet0/0/4]shutdown 
[SW1]display smart-link group 1
Smart Link group 1 information :
  Smart Link group was enabled
  Wtr-time is: 30 sec.
  There is no Load-Balance
  There is no protected-vlan reference-instance
  DeviceID: 4c1f-cc5a-5958  Control-vlan ID: 10
  Member                  Role   State    Flush Count Last-Flush-Time
  GigabitEthernet0/0/1    Master Active   4           2023/01/25 20:04:55 UTC-08:00 
  GigabitEthernet0/0/2    Slave  Inactive 0           0000/00/00 00:00:00 UTC+00:00 

2）在SW2上启用Monitor Link组1，配置上行接口G0/0/4，下行接口G0/0/3

[SW2]monitor-link group 1
[SW2-mtlk-group1]port GigabitEthernet 0/0/3 downlink
[SW2-mtlk-group1]port GigabitEthernet 0/0/4 uplink

3）SW2上行接口GigabitEthernet 0/0/4 shutdown，查看Smart Link，完成主从切换。

[SW2]interface GigabitEthernet 0/0/4
[SW2-GigabitEthernet0/0/4]shutdown 

[SW1]display smart-link group 1
Smart Link group 1 information :
  Smart Link group was enabled
  Wtr-time is: 30 sec.
  There is no Load-Balance
  There is no protected-vlan reference-instance
  DeviceID: 4c1f-cc5a-5958  Control-vlan ID: 10
  Member                  Role   State    Flush Count Last-Flush-Time  
  GigabitEthernet0/0/1    Master Inactive 5           2023/01/25 20:18:24 UTC-08:00 
  GigabitEthernet0/0/2    Slave  Active   0           0000/00/00 00:00:00 UTC+00:00 

4）修改Monitor Link组的回切时间为10秒。

SW2的上行GigabitEthernet 0/0/4端口undo shutdown后，SW1在10S后重新切回主链路。
[SW2-mtlk-group1]timer recover-time 10
[SW2]interface GigabitEthernet 0/0/4
[SW2-GigabitEthernet0/0/4]undo shutdown 
[SW1]display smart-link group 1
Smart Link group 1 information :
  Smart Link group was enabled
  Wtr-time is: 30 sec.
  There is no Load-Balance
  There is no protected-vlan reference-instance
  DeviceID: 4c1f-cc5a-5958  Control-vlan ID: 10
  Member                  Role   State    Flush Count Last-Flush-Time
  GigabitEthernet0/0/1    Master Active   6           2023/01/25 20:25:17 UTC-08:00 
  GigabitEthernet0/0/2    Slave  Inactive 0           0000/00/00 00:00:00 UTC+00:00 

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