Chapter 14
Configuring STP
Configuring Spanning-Tree Features
These sections describe how to configure spanning-tree features:
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Default Spanning-Tree Configuration
Table 14-3
Table 14-3 Default Spanning-Tree Configuration
Feature
Enable state
Spanning-tree mode
Switch priority
Spanning-tree port priority (configurable on a per-interface basis)
Spanning-tree port cost (configurable on a per-interface basis)
Spanning-tree VLAN port priority (configurable on a per-VLAN basis)
Spanning-tree VLAN port cost (configurable on a per-VLAN basis)
Spanning-tree timers
78-11380-10
Default Spanning-Tree Configuration, page 14-11
Spanning-Tree Configuration Guidelines, page 14-12
Changing the Spanning-Tree Mode, page 14-13
Disabling Spanning Tree, page 14-14
Configuring the Root Switch, page 14-14
Configuring a Secondary Root Switch, page 14-16
Configuring the Port Priority, page 14-17
Configuring the Path Cost, page 14-19
Configuring the Switch Priority of a VLAN, page 14-20
Configuring Spanning-Tree Timers, page 14-21
shows the default spanning-tree configuration.
(required)
(optional)
(optional)
(optional)
(optional)
(optional)
(optional)
(optional)
Default Setting
Enabled on VLAN 1.
For more information, see the
Spanning-Tree Instances" section on
page
PVST+. (Rapid PVST+ and MSTP are
disabled.)
32768.
128.
1000 Mbps: 4.
100 Mbps: 19.
10 Mbps: 100.
128.
1000 Mbps: 4.
100 Mbps: 19.
10 Mbps: 100.
Hello time: 2 seconds.
Forward-delay time: 15 seconds.
Maximum-aging time: 20 seconds.
Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
Configuring Spanning-Tree Features
"Supported
14-9.
14-11