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Catalyst 3550 Multilayer Switch Software Configuration Guide
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Chapter26 Configuring Fallback Bri dging Configuring Fallback Bridging
Beginning in privileged EXEC mode, follow these steps to filter by the MAC-layer address:
To disable the frame forwarding ability, use the no bridge bridge-group address mac-address global
configuration command.
This example shows how to forward a frame with MAC address 08 00.cb00.45e9 through an interface in
bridge group 1:
Switch(config)# bridge 1 address 0800.cb00.45e9 forward gigabitethernet0/1
Adjusting Spanning-Tree Parameters
You might need to adjust certain spanning-tree parameters if the default values ar e not suita bl e for you r
switch configuration. Parameters affecting the entire spannin g tree are conf igu red with v ariati ons o f the
bridge global configuration command. Interface-specific para met ers a re con fi gured w it h vari ati on s of
the bridge-group interface configuration command.
You can adjust spanning-tree parameters by performing any of the tasks in these sections:
•Changing the Switch Priority, page 26-8
•Changing the Interface Priority, page 26-8
•Assigning a Path Cost, page 26-9
•Adjusting BPDU Intervals, page 26-10
•Disabling the Spanning Tree on an Interface, page 26-12
Note Only network administrators with a good understanding of h ow sw it ches and STP fun ction sh ould
make adjustments to spanning-tree parameters. Poorly planned adjust ment s ca n have a ne gat ive
impact on performance. A good source on switching is the I EE E 80 2.1 d sp ec ific ati on ; fo r more
information, refer to the “References and Recommended Reading” appendix in the Cisco IOS
Configuration Fundamentals Command Reference.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 bridge bridge-group address mac-address
{forward | discard} [interface-id]Specify the MAC address to discard or forward.
•For bridge-group, specify the bridge group number. The range is 1
to 255.
•For address mac-address, specify the MAC-layer destination
address to be filtered.
•Specify forward if you want the frame destined to the specified
interface to be forwarded. Specify discard if you want the frame to
be discarded.
•(Optional) For interface-id, specify the interface on which the
address can be reached.
Step3 end Return to privileged EXEC mode.
Step4 show running-config Verify your entry.
Step5 copy running-config startup-config (Optional) Save your entry in the configuration file.