Monitoring And Maintaining Ip Addressing - Cisco WS-C3550-12G Software Configuration Manual

Chapter 22 Configuring IP Unicast Routing
Beginning in privileged EXEC mode, follow these steps to use the bridging spanning-tree database to
flood UDP datagrams:
Command
Step 1 configure terminal
Step 2
ip forward-protocol spanning-tree
Step 3
end
Step 4 show running-config
Step 5
copy running-config startup-config
Use the no ip forward-protocol spanning-tree global configuration command to disable the flooding
of IP broadcasts.
In the Catalyst 3550 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:
Command
Step 1 configure terminal
Step 2
ip forward-protocol turbo-flood
Step 3
end
Step 4
show running-config
Step 5 copy running-config startup-config
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.
commands for clearing contents.
Table 22-3 Commands to Clear Caches, Tables, and Databases
Command
clear arp-cache
clear host {name | *}
clear ip route {network [mask] |*}
78-11194-03
Purpose
Enter global configuration mode.
Use the bridging spanning-tree database to flood UDP datagrams.
Return to privileged EXEC mode.
Verify your entry.
(Optional) Save your entry in the configuration file.
Purpose
Enter global configuration mode
Use the spanning-tree database to speed up flooding of UDP
datagrams.
Return to privileged EXEC mode.
Verify your entry.
(Optional) Save your entry in the configuration file.
Purpose
Clear the IP ARP cache and the fast-switching cache.
Remove one or all entries from the host name and the address cache.
Remove one or more routes from the IP routing table.
Catalyst 3550 Multilayer Switch Software Configuration Guide
Configuring IP Addressing
Table 22-3 lists the
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