Dell SmartFabric OS10 User Guide Release 10.5.4

Disable dynamic MAC learning

Use the mac-learn disable command to disable MAC learning on the physical, LAG, and virtual interfaces.

When MAC learning is disabled on a port, all the dynamic and sticky MAC addresses that are learnt are flushed and only the configured static MAC addresses are retained. All the packets with new source MAC address received on the MAC learn disabled port is handled based on the MAC address disable violation action configured on that port.

This feature is only supported on port-security enabled ports. On port-security enabled ports, both MAC address learning limit and MAC address learning disable features are mutually exclusive. When configurations for both features are present, MAC learn disable configuration takes precedence over MC learn limit configuration. However, when MAC address learning is enabled, MAC learning happens based on the MAC learn limit configured.

MAC learning disable violation actions

When new source MAC addresses are received on the MAC learn disabled port, you can configure different violation actions as follows:

• Log—A single log message is displayed on console indicating the port on which MAC learning disable violation occurred and drop that violated packet in the hardware. If more violations occur on the same source port, all violation logs are sent to the syslog server, if configured. This is the default violation action.
• Shutdown the port.
• Forward the packet—Do not learn the MAC address but forward the packet.
• Drop the packet—Packets received with a new source MAC address are dropped.