Enabling MAC Address-triggered ARP Entry Update
Context
Devices on an Ethernet LAN send and receive Ethernet data frames based on MAC addresses. To map IP addresses to MAC addresses, the Address Resolution Protocol (ARP) is used. When two devices on different network segments communicate with each other, they need to map IP addresses to MAC addresses and outbound interfaces according to ARP entries. MAC address-triggered ARP entry update enables a switch to update the outbound interface in an ARP entry immediately after the outbound interface in the corresponding MAC address entry changes.
Procedure
- Run system-view
The system view is displayed.
- Run mac-address update arp
The MAC address-triggered ARP entry update function is enabled.
By default, the MAC address-triggered ARP entry update function is disabled.
- Only the S5720-EI, S5720-HI, S5720I-SI, S5720S-SI, S5720-SI, S5735-S, S5735S-S, S5735-S-I, S5730-HI, S5730S-EI, S5730-SI, S5731-H, S5731-S, S5731S-H, S5731S-S, S5732-H, S5720-LI, S5720S-LI, S6720-LI, S6720S-LI, S6720-EI, S6720-HI, S6720S-EI, S6720S-SI, S6720-SI, S6730-H, S6730S-H, S6730-S, and S6730S-S support this command.
- This function takes effect only for dynamic ARP entries. Static ARP entries are not updated when the corresponding MAC address entries change.
- The MAC address-triggered ARP entry update function does not take effect after ARP entry fixing is enabled using the arp anti-attack entry-check enable command.
- After the MAC address-triggered ARP entry update function is enabled, the switch updates an ARP entry only when the outbound interface in the corresponding MAC address entry changes.