The arp learning multicast enable command globally enables a device to learn ARP entries with multicast MAC addresses.
The undo arp learning multicast enable command globally disables a device from learning ARP entries with multicast MAC addresses.
By default, a device is globally disabled from learning ARP entries with multicast MAC addresses.
Usage Scenario
An IP address may map a multicast MAC address. In this case, a network administrator has to configure a static ARP entry. After a device is enabled to learn ARP entries with multicast MAC addresses, the device can generate dynamic ARP entries. This reduces a network administrator's workload and decreases network operation and maintenance costs.
Precautions
After a device is enabled to learn ARP entries with multicast MAC addresses, the device may be attacked by ARP attack packets with multicast MAC addresses.
The arp learning multicast enable and arp learning multicast disable commands can be used together on an interface to precisely control the range of ARP entries with multicast MAC addresses to be learned.