Dell C1048P Port Extender Networking Configuration Guide for the C9000 Series - Page 465

clear arp-cache [interface | ip ip-address] [no-refresh] - ip ip-address (OPTIONAL): enter the keyword ip then the IP address of the ARP entry you wish to clear. - no-refresh (OPTIONAL): enter the keywords no-refresh to delete the ARP entry from CAM. Or to specify which dynamic ARP entries you want to delete, use this option with interface or ip ip-address. - For a port channel interface, enter the keywords port-channel then a number. - For a 10-Gigabit Ethernet interface, enter the keyword TenGigabitEthernet then the slot/port information. - For a 40-Gigabit Ethernet interface, enter the keyword fortyGigE then the slot/port information. - For a port extender 1-Gigabit Ethernet interface enter the keyword peGigE then the pe-id/pe-stack-unit-id/port- number information. - For a VLAN interface, enter the keyword vlan then a number between 1 and 4094. NOTE: Transit traffic may not be forwarded during the period when deleted ARP entries are resolved again and re-installed in CAM. Use this option with extreme caution. ARP Learning via Gratuitous ARP Gratuitous ARP can mean an ARP request or reply. During ARP learning via gratuitous ARP, the gratuitous ARP is a request. A gratuitous ARP request is an ARP request that is not needed according to the ARP specification, but one that hosts may send to: • detect IP address conflicts • inform switches of their presence on a port so that packets can be forwarded • update the ARP table of other nodes on the network in case of an address change In the request, the host uses its own IP address in the Sender Protocol Address and Target Protocol Address fields. When a gratuitous ARP is received, the system installs an ARP entry on all three CPUs. Enabling ARP Learning via Gratuitous ARP To enable ARP learning via gratuitous ARP, use the following command. • Enable ARP learning via gratuitous ARP. CONFIGURATION mode arp learn-enable IPv4 Routing 465