Cisco Catalyst 2950 - Configuring Basic STP Features; Default STP Configuration

9-20
Catalyst 2950 Desktop Switch Software Configuration Guide
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Chapter 9 Configuring STP
Configuring Basic STP Features
Configuring Basic STP Features
These sections include basic STP configuration information:
• Default STP Configuration, page 9-20
• Disabling STP, page 9-21
• Configuring the Root Switch, page 9-21
• Configuring a Secondary Root Switch, page 9-23
• Configuring STP Port Priority, page 9-24
• Configuring STP Path Cost, page 9-25
• Configuring the Switch Priority of a VLAN, page 9-26
• Configuring the Hello Time, page 9-27
• Configuring the Forwarding-Delay Time for a VLAN, page 9-27
• Configuring the Maximum-Aging Time for a VLAN, page 9-28
• Configuring STP for Use in a Cascaded Cluster, page 9-28
• Displaying STP Status, page 9-29
For advanced configuration information, see the “Configuring Advanced STP Features” section on
page 9-30.
Default STP Configuration
Table 9-2 shows the default STP configuration.
Table 9-2 Default STP Configuration
Feature Default Setting
Enable state Enabled on VLAN 1.
Up to 128 spanning-tree instances can be
enabled.
Switch priority 32768.
Spanning-tree port priority (configurable on a per-interface basis—used on
interfaces configured as access ports)
128.
Spanning-tree port cost (configurable on a per-interface basis—used on
interfaces configured as access ports)
1000 Mbps: 4.
100 Mbps: 19.
10 Mbps: 100.
Spanning-tree VLAN port priority (configurable on a per-VLAN basis—used on
interfaces configured as trunk ports)
128.
Spanning-tree VLAN port cost (configurable on a per-VLAN basis—used on
interfaces configured as trunk ports)
1000 Mbps: 4.
100 Mbps: 19.
10 Mbps: 100.
Hello time 2 seconds.