On EX4100 switches, excessive jnxl2aldInterfaceMacLimit SNMP traps may be generated when the configured per-interface MAC learning limit is reached.

The devices were connected to daisy-chained IP cameras were learning more MAC addresses than the configured limit allowed. As a result, MAC learning events triggered continuous log messages and packet drops.

The issue was caused by a VLAN-level interface MAC limit of 3 MAC addresses configured with the action drop-and-log. When additional MAC addresses were learned on the affected ports, packets were dropped and SNMP traps were generated.

Approximately 100 jnxl2aldInterfaceMacLimit SNMP traps per day were received from the switches

The following messages were observed in the logs:

L2ALD_MAC_LIMIT_EXCEEDED_IFBD: Limit on learned MAC addresses exceeded

current count is 3 DROPPING THE PACKET

The affected interfaces were connected to daisy-chained IP cameras, resulting in more than three source MAC addresses being learned on the same access port. The VLAN-level MAC limit configuration was therefore insufficient for the deployment requirements and caused:

• Packet drops.
• Continuous MAC limit traps.
• Excessive log generation

To resolve, configure a higher interface-specific MAC limit on the affected ports , under the VLAN context:

set vlans <vlan-name> switch-options interface ge-0/0/0.0 interface-mac-limit 5 packet-action drop-and-log

After increasing the MAC limit from 3 to 5 for specific ports under the vlan, the customer confirmed:

• MAC limit messages stopped.
• Daisy-chained IP cameras were no longer blocked.
• The issue was fully resolved.