Configuring a System MAC Address Switching Delay
Context
A stack communicates with other network devices as one device and has a unique MAC address. This MAC address is the stack MAC address. Generally, the MAC address of the master switch is used as the stack MAC address.
If the owner of the stack MAC address leaves the stack, switching of the stack MAC address will cause traffic interruption. You can configure a system MAC address switching delay to reduce the impact of switching of the stack MAC address on services.
- If the stack MAC address is the MAC address of the master switch
and the master switch fails or leaves the stack, the following may
occur:
- When no system MAC address switching delay is configured, the MAC address of the new master switch is immediately used as the stack MAC address. By default, a system MAC address switching delay is configured and the switching delay is set to 10 minutes.
- When a system MAC address switching delay is configured, the new master switch uses its own MAC address as the stack MAC address if the old master switch does not rejoin the stack within the switching delay; the stack MAC address remains unchanged if the old master switch rejoins the stack as a slave switch within the switching delay.
- If the stack MAC address is the MAC address of a slave switch, the MAC address of the master switch is used as the stack MAC address after the slave switch leaves the stack and does not rejoin the stack within the switching delay.
Procedure
- Run the system-view command to enter the system view.
- Run the stack timer
mac-address switch-delay delay-time command to configure a system MAC address switching delay.
By default, the system MAC address switching delay is 10 minutes.
When the delay time is set to 0, the stack MAC address will not change after the owner of the stack MAC address leaves the stack. If you run the undo stack timer mac-address switch-delay command, the stack MAC address will change immediately after the owner of the stack MAC address leaves the stack.
When the system is configured to switch the system MAC address immediately, the system uses the MAC address of the new master switch as the system MAC address immediately when the previous master switch fails or leaves the stack. This may cause protocols such as LACP and STP to flap, affecting services.