HP 2920 Series User Manual

addressing for a packet and is ready to forward the packet, the device checks the IP forwarding
cache for an entry to the packet's destination.
• If the cache contains an entry with the destination IP address, the device uses the information
in the entry to forward the packet out the ports listed in the entry. The destination IP address
is the address of the packet's final destination. The port numbers are the ports through which
the destination can be reached.
• If the cache does not contain an entry, the software can create an entry in the forwarding
cache.
Each entry in the IP forwarding cache has an age timer. The age interval depends on the number
of entries in the table. The age timer ranges from 12 seconds (full table) to 36 seconds (empty
table.) Entries are aged only if they are not being used by traffic. If you have an entry that is always
being used in hardware, it will never age. If there is no traffic, it will age in 12 to 36 seconds.
The age timer is not configurable.
NOTE: You cannot add static entries to the IP forwarding cache.
IP route exchange protocols
The switch supports the RIP IP route exchange protocol.
This protocol provides routes to the IP route table and is disabled by default. For configuration
information, see “Configuring RIP parameters” (page 52).
IP global parameters for routing switches
Table 3 lists the IP global parameters and the page where you can find more information about
each parameter.
Table 3 IP global parameters for routing switches
See pageDefaultDescriptionParameter
42EnabledA standard IP mechanism
that routers use to learn the
Address Resolution Protocol
(ARP)
MAC address of a device
on the network. The router
sends the IP address of a
device in the ARP request
and receives the device's
MAC address in an ARP
reply.
N/AFive minutesThe amount of time the
device keeps a MAC
ARP age
address learned through
ARP in the device's ARP
cache. The device resets the
timer to zero each time the
ARP entry is refreshed and
removes the entry if the timer
reaches the ARP age. (Can
be set using the menu
interface to be as long as
1440 minutes. Go to Menu
> Switch Configuration > IP
Config.)
See “ARP age timer”
(page 40).
See the chapter
"Configuring IP Addressing"
64 hopsThe maximum number of
routers (hops) through which
Time to Live (TTL)
38 IP Routing Features

HP 2920 Series Specifications

General

Brand	HP
Model	2920 Series
Category	Switch
Language	English