32-17
Cisco ME 3400 EthernetAccess Switch SoftwareConfiguration Guide
78-17058-01
Chapter32 Configuring IP Unicast Routing Enabling IPv4 Unicast Routing

Monitoring and Maintaining IP Addressing

When the contents of a particular cache, table, or database have become or are suspected to be invalid,
you can remove all its contents by using the clear privileged EXEC commands. Table32-2 lists the
commands for clearing contents.
You can display specific statistics, such as the contents of IP routing tables, caches, and databases; the
reachability of nodes; and the routing path that packets are taking through the network. Table 32- 3 lists
the privileged EXEC commands for displaying IP statistics.
Enabling IPv4 Unicast Routing
By default, the switch is in Layer 2 switching mode and IP routing is disabled. To use the Layer3
capabilities of the switch, you must enable IP routing.
Beginning in privileged EXEC mode, follow these steps to enable IP routing:
Table32-2 Commands to Clear Caches, Tables, and Databases
Command Purpose
clear arp-cache Clear the IP ARP cache and the fast-switching cache.
clear host {name | *} Remove one or all entries from the hostname and the address cache.
clear ip route {network [mask] |*} Remove one or more routes from the IP routing table.
Table32-3 Commands to Display Caches, Tables, and Databases
Command Purpose
show arp Display the entries in the ARP table.
show hosts Display the default domain name, style of lookup service, name server hosts,
and the cached list of hostnames and addresses.
show ip aliases Display IP addresses mapped to TCP ports (aliases).
show ip arp Display the IP ARP cache.
show ip interface [interface-id] Display the IP status of interfaces.
show ip irdp Display IRDP values.
show ip masks address Display the masks used for network addresses and the number of sub nets
using each mask.
show ip redirects Display the address of a default gateway.
show ip route [address [mask]] | [protocol] Display the current state of the routing table.
show ip route summary Display the current state of the routing table in summary form.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 ip routing Enable IP routing.