arp

Profile Config Commands

Adds a static ARP (Address Resolution Protocol) IP address in the ARP cache

The ARP protocol maps an IP address to a hardware MAC address recognized on the network. ARP provides protocol rules for making this correlation and providing address conversion in both directions.

When an incoming packet destined for a host arrives, ARP finds a physical host or MAC address that matches the IP address. ARP looks in its ARP cache and, if it finds the address, provides it so the packet can be converted to the right packet length, formatted, and sent to its destination. If no entry is found for the IP address, ARP broadcasts a request packet in a special format on the LAN to locate a device that recognizes the IP address. A device that recognizes the IP address as its own returns a reply indicating it. ARP updates the ARP cache for future reference and then sends the packet to the MAC address that replied.

Supported on the following devices:

Syntax

arp [<IP>|timeout]
arp <IP> <MAC> arpa [<L3-INTERFACE-NAME>|pppoe1|vlan <1-4094>|wwan1|serial <1-4> <1-1> <1-1>] {dhcp-server|router}
arp timeout <15-86400>

Parameters

arp <IP> <MAC> arpa [<L3-INTERFACE-NAME>|pppoe1|vlan <1-4094>|wwan1|serial <1-4> <1-1> <1-1>] {dhcp-server|router}
arp <IP> Adds a static ARP IPv4 address in the ARP cache
  • <IP> – Specify the static IP address.
<MAC> Specify the MAC address associated with the IP and the Switch Virtual Interface (SVI).
arpa Sets ARP encapsulation type to ARPA
<L3-INTERFACE-NAME> Configures static ARP entry for a specified router interface
  • <L3-INTERFACE-NAME> – Specify the router interface name.
pppoe1 Configures static ARP entry for PPP over Ethernet interface
vlan <1-4094> Configures static ARP entry for a VLAN interface
  • <1-4094> – Specify a SVI VLAN ID from 1 - 4094.
wwan1 Configures static ARP entry for Wireless WAN interface
{dhcp-server|router} The following keywords are common to all off the above interface types:
  • dhcp-server – Optional. Sets ARP entries for a DHCP server
  • router – Optional. Sets ARP entries for a router
arp timeout <15-86400>
arp timeout <15-86400> Sets ARP entry timeout
  • <TIME> – Sets the ARP entry timeout in seconds. Specify a value from 15 - 86400 seconds. The default is 3600 seconds.

Example

nx9500-6C8809(config-profile-default-rfs4000)#arp timeout 2000

nx9500-6C8809(config-profile-default-rfs4000)#show context
profile rfs4000 default-rfs4000
 bridge vlan 1
  bridging-mode isolated-tunnel
  ip igmp snooping
  ip igmp snooping querier
 arp timeout 2000
 crypto ikev1 policy ikev1-default
  isakmp-proposal default encryption aes-256 group 2 hash sha
 crypto ikev2 policy ikev2-default
  isakmp-proposal default encryption aes-256 group 2 hash sha
 crypto ipsec transform-set default esp-aes-256 esp-sha-hmac
 crypto ikev1 remote-vpn
 crypto ikev2 remote-vpn
 crypto auto-ipsec-secure
 interface me1
 interface ge1
  ip dhcp trust
  qos trust dscp
  qos trust 802.1p
 interface ge2
  ip dhcp trust
--More--
nx9500-6C8809(config-profile-default-rfs4000)#

Related Commands

no Removes an entry from the ARP cache