Troubleshooting Tip: FortiSwitch MAC Address Flushing

A FortiSwitch is designed to optimize network resources. It periodically removes MAC addresses from its address table if:

Device Inactivity: The connected device has been idle for a period longer than the configured MAC aging interval.

Device Reboot: The connected device restarts, causing the switch to relearn its MAC address.

Temporary Workaround:

To prevent immediate MAC address deletion, you can temporarily set the MAC aging interval to 0 by executing the below commands:

config switch global
    set mac-aging-interval 0
end

Permanent Solution:

For a long-term solution, address the root cause of the issue:

• Device Replacement: If the device is faulty or unreliable, consider replacing it with a more stable device.
• Device-Side Troubleshooting: Investigate the connected device to ensure it's functioning correctly and sending regular traffic.