35-17
Cisco ME 3400 Ethernet Access Switch Software Configuration Guide
OL-9639-06
Chapter 35 Configuring IP Unicast Routing Configuring IP Addressing
Use the no ip forward-protocol spanning-tree global configuration command to disable the flooding
of IP broadcasts.
In the switch, the majority of packets are forwarded in hardware; most packets do not go through the
switch CPU. For those packets that do go to the CPU, you can speed up spanning tree-based UDP
flooding by a factor of about four to five times by using turbo-flooding. This feature is supported over
Ethernet interfaces configured for ARP encapsulation.
Beginning in privileged EXEC mode, follow these steps to increase spanning-tree-based flooding:
To disable this feature, use the no ip forward-protocol turbo-flood global configuration command.
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. Table 35-2 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 35-3 lists
the privileged EXEC commands for displaying IP statistics.
Command Purpose
Step 1 configure terminal Enter global configuration mode
Step 2 ip forward-protocol turbo-flood Use the spanning-tree database to speed up flooding of UDP datagrams.
Step 3 end Return to privileged EXEC mode.
Step 4 show running-config Verify your entry.
Step 5 copy running-config startup-config (Optional) Save your entry in the configuration file.
Tab le 35-2 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.
Tab le 35-3 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.