MAC Address Learning Control
When hackers send a large number of packets with different source MAC addresses to a device, useless MAC addresses will consume MAC address entry resources of the device. As a result, the device cannot learn source MAC addresses of valid packets. The device broadcasts the packets that do not match MAC address entries, wasting bandwidth resources.
The device provides the following MAC address learning control methods to address the preceding issue:
Disabling MAC address learning on a VLAN or an interface
Limiting the number of learned MAC address entries on a VLAN or an interface
| MAC Address Learning Control Method | Principle | Application Scenario |
|---|---|---|
Disabling MAC address learning on a VLAN or an interface |
After MAC address learning is disabled on a VLAN or an interface, the device does not learn new dynamic MAC address entries on the VLAN or interface. The dynamic MAC address entries learned before are aged out when the aging time expires. They can also be manually deleted using commands. |
|
Limiting the number of learned MAC address entries on a VLAN or an interface |
The device can only learn a specified number of MAC address entries on a VLAN or an interface. When the number of learned MAC address entries reaches the limit, the device reports an alarm to notify the network administrator. After that, the device cannot learn new MAC address entries on the VLAN or interface and discards the packets with source MAC addresses out of the MAC address table. |