interface) before the system verifies that sufficient CAM space exists. If the CAM check fails, a messageis displayed:%E90MH:5 %ACL_AGENT-2-ACL_AGENT_LIST_ERROR: Unable to apply access-list Mac-Limit on TenGigabitEthernet 4/24In this case, the configuration is still present in the running-config and show output. Remove theconfiguration before re-applying a MAC learning limit with a lower value. Also, ensure that you can viewthe Syslog messages on your session.NOTE: The CAM-check failure message beginning in Dell Networking OS version 8.3.1.0 is differentfrom versions 8.2.1.1 and earlier, which read:% Error: ACL returned error% Error: Remove existing limit configuration if it was configured beforeSetting the MAC Learning LimitTo set a MAC learning limit on an interface, use the following command.• Specify the number of MAC addresses that the system can learn off a Layer 2 interface.INTERFACE modemac learning-limit address_limitThree options are available with the mac learning-limit command:– dynamic– no-station-move– station-moveNOTE: An SNMP trap is available for mac learning-limit station-move. No other SNMPtraps are available for MAC Learning Limit, including limit violations.mac learning-limit DynamicThe MAC address table is stored on the Layer 2 forwarding information base (FIB) region of the CAM.The Layer 2 FIB region allocates space for static MAC address entries and dynamic MAC address entries.When you enable MAC learning limit, entries created on this port are static by default. When youconfigure the dynamic option, learned MAC addresses are stored in the dynamic region and are subjectto aging. Entries created before this option is set are not affected.Dell Networking OS Behavior: If you do not configure the dynamic option, the systems do not detectstation moves in which a MAC address learned off of a MAC-limited port is learned on another port onsame line card. Therefore, Dell Networking OS does not take any configured station-move violationaction. When a MAC address is relearned on any other line card (any line card except the one to whichthe original MAC-limited port belongs), the station-move is detected and the system takes the configuredthe violation action.448 Layer 2
