Riverstone Networks WICT1-12 - Manual (Page 183)

Riverstone Networks RS Switch Router User Guide Release 8.0 11-5
IP Routing Configuration Guide Configuring Address Resolution Protocol (ARP)
11.4 CONFIGURING ADDRESS RESOLUTION
PROTOCOL (ARP)
The RS allows you to configure Address Resolution Protocol (ARP) table entries and parameters. ARP is used to
associate IP addresses with media or MAC addresses. Taking an IP address as input, ARP determines the associated
MAC address. Once a media or MAC address is determined, the IP address/media address association is stored in an
ARP cache for rapid retrieval. Then the IP datagram is encapsulated in a link-layer frame and sent over the network.
11.4.1 Configuring ARP Cache Entries
To create an ARP entry for the IP address 10.8.1.2 at port et.4.7 for 15 seconds:
To create a permanent ARP entry for the host nfs2 at port et.3.1:
To remove the ARP entry for the host 10.8.1.2 from the ARP table:.
To clear the entire ARP table.
If the Startup configuration file contains
arp add
commands, the Control Module re-adds the ARP entries even if
you have cleared them using the
arp clear
command. To permanently remove an ARP entry, use the
negate
command or
no
command to remove the entry.
11.4.2 Unresolved MAC Addresses for ARP Entries
When the RS receives a packet for a host whose MAC address it has not resolved, the RS tries to resolve the next-hop
MAC address by sending ARP requests. Five requests are sent initially for each host, one every second.
You can configure the RS to drop packets for hosts whose MAC addresses the RS has been unable to resolve. To enable
dropping of packets for hosts with unresolved MAC addresses:
When you enable packets to be dropped for hosts with unresolved MAC addresses, the RS will still attempt to
periodically resolve these MAC addresses. By default, the RS sends ARP requests at 5-second intervals to try to
resolve dropped entries.
rs# arp add 10.8.1.2 mac-addr 08:00:20:a2:f3:49 exit-port et.4.7
keep-time 15
rs(config)# arp add nfs2 mac-addr 080020:13a09f exit-port et.3.1
rs# arp clear 10.8.1.2
rs# arp clear all
rs# arp set drop-unresolved enabled