HP J9729A User Manual

device's MAC address or the MAC address of the router interface that answered an ARP request
on behalf of the device, using proxy ARP.
ARP cache
The ARP cache contains dynamic (learned) entries. The software places a dynamic entry in the
ARP cache when the routing switch learns a device's MAC address from an ARP request or ARP
reply from the device.
The software can learn an entry when the switch or routing switch receives an ARP request from
another IP forwarding device or an ARP reply. Here is an example of a dynamic entry:
Example 15 ARP cache dynamic entry
IP Address MAC Address Type Port
1 207.95.6.102 0800.5afc.ea21 Dynamic 6
Each entry contains the destination device's IP address and MAC address.
To configure other ARP parameters, see “Configuring ARP parameters” (page 42).
IP route table
The IP route table contains routing paths to IP destinations.
NOTE: The default gateway, which you specify when you configure the basic IP information on
the switch, is used only when routing is not enabled on the switch.
Routing paths
The IP route table can receive the routing paths from the following sources:
• Directly-connected destination, which means there are no router hops to the destination
• Static IP route, which is a user-configured route
• Route learned through RIP
Administrative distance
The IP route table contains the best path to a destination. When the software receives paths from
more than one of the sources listed above, the software compares the administrative distance of
each path and selects the path with the lowest administrative distance. The administrative distance
is a protocol-independent value from 1 to 255.
The IP route table is displayed by entering the show ip route command from any context level
in the console CLI. Here is an example of an entry in the IP route table:
Example 16 IP route table entry
Destination Gateway VLAN Type Sub-Type Metric Dist.
-------------- ----------- ----- --------- ---------- -------- ----
10.10.10.1/32 10.10.12.1 connected 1 0
Each IP route table entry contains the destination's IP address and subnet mask and the IP address
of the next-hop router interface to the destination. Each entry also indicates route type, and for
OSPF routes, the subtype, and the route's IP metric (cost.) The type indicates how the IP route table
received the route.
To configure a static IP route, see “Configuring a static IP route” (page 47).
IP forwarding cache
The IP forwarding cache provides a fast-path mechanism for forwarding IP packets. The cache
contains entries for IP destinations. When an HP routing switch has completed processing and
Overview 37

HP J9729A Specifications

General

Brand	HP
Model	J9729A
Category	Switch
Language	English