Configuring ARP

Configuring Static ARP

Static ARP entries record the fixed mapping between IP and MAC addresses. They are configured manually.

Enabling a Device to Learn Multicast MAC Addresses and Generate ARP Entries

If a device is enabled to learn multicast MAC addresses, it can generate ARP entries after receiving ARP packets carrying multicast MAC addresses as source MAC addresses. This section describes how to enable a device to learn multicast MAC addresses and generate ARP entries.

Optimizing Dynamic ARP

Dynamic ARP is enabled without the need to be enabled. To optimize this function, you can modify some dynamic ARP parameters.

Configuring a Device to Delete Dynamic ARP Entries after a Delay

By default, a device deletes dynamic ARP entries immediately after a VLAN interface goes Down. If you configure a device to delete dynamic ARP entries after a delay, it sends ARP detection packets and then deletes or updates ARP entries based on whether it receives ARP reply packets within the ARP aging time.

Configuring ARP Automatic Scanning and Fixed ARP

ARP automatic scanning and fixed ARP enable a device to generate dynamic ARP entries and convert the dynamic ARP entries to static ARP entries.

Configuring the ARP Proxy

Proxy ARP implements communication between devices on the same network segment but on different physical networks.

Configuring Gratuitous ARP

A gratuitous ARP packet is a special ARP packet whose sender and destination IP addresses are both the local IP addresses, the sender MAC address is the MAC address of the local MAC address, and destination MAC address is the broadcast address. Configuring gratuitous ARP enables a device to proactively learn and send gratuitous ARP packets.

Preventing Attacks on ARP Entries

Measures for preventing ARP entry attacks are strict ARP entry learning, ARP entry restriction, and enabling alarm functions for potential attack behaviors.