Enabling Proxy Arp; Clearing Arp Cache; Arp Learning Via Gratuitous Arp - Dell S6100 Configuration Manual

To view the static entries in the ARP cache, use the show arp static command in EXEC privilege mode.
Dell#show arp
Protocol Address
--------------------------------------------------------------------------------
Internet 10.1.2.4
Dell#

Enabling Proxy ARP

By default, Proxy ARP is enabled. To disable Proxy ARP, use the no proxy-arp command in the interface mode.
To re-enable Proxy ARP, use the following command.
• Re-enable Proxy ARP.
INTERFACE mode
ip proxy-arp
To view if Proxy ARP is enabled on the interface, use the show config command in INTERFACE mode. If it is not listed in the show
config command output, it is enabled. Only non-default information is displayed in the show config command output.

Clearing ARP Cache

To clear the ARP cache of dynamically learnt ARP information, use the following command.
• Clear the ARP caches for all interfaces or for a specific interface by entering the following information.
EXEC privilege
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 10-Gigabit Ethernet interface, enter the keyword TenGigabitEthernet then the stack/slot/port/subport information.
• For a 25-Gigabit Ethernet interface, enter the keyword twentyFiveGigE then the stack/slot/port/subport information.
• For a 40-Gigabit Ethernet interface, enter the keyword fortyGigE then the stack/slot/port[/subport] information.
• For a 50-Gigabit Ethernet interface, enter the keyword fiftyGigE then the stack/slot/port/subport information.
• For a 100-Gigabit Ethernet interface, enter the keyword hundredGigE then the stack/slot/port information.
• For a port channel interface, enter the keywords port-channel then a number.
• For a VLAN interface, enter the keyword vlan then a number from 1 to 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.
In the context of ARP learning via gratuitous ARP on Dell Networking OS, 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
422 IPv4 Routing
Age(min) Hardware Address
17 08:00:20:b7:bd:32
Interface VLAN CPU
Ma 1/1 - CP