Preventing MAC Address Flapping Between Interfaces with the Same Priority
Context
Preventing MAC address flapping between interfaces with the same priority can improve network security.
After this configuration is complete, the following issue may occur: If a network device (such as a server) connected to an interface of the switch is powered off and the same MAC address is learned on another interface, the switch cannot learn the correct MAC address on the original interface after the network device is powered on.
Only the S5720-EI, S5720-HI, S5730-HI, S5731-H, S5731-S, S5731S-H, S5731S-S, S5732-H, S6720-EI, S6720-HI, S6720S-EI, S6730-H, S6730S-H, S6730-S, and S6730S-S support this configuration.
Procedure
- Run system-view
The system view is displayed.
- Run undo mac-learning priority priority-id allow-flapping
The device is configured to prevent MAC address flapping between interfaces with the same priority.
By default, the device allows MAC address flapping between interfaces with the same priority.
- Run mac-learning priority flapping-defend action discard
The switch discards packets when configured to prohibit MAC address flapping.
By default, the action is forward when configured to prohibit MAC address flapping.