10-21
Catalyst 3550 Multilayer Switch Software Configuration Guide
78-11194-03
Chapter 10 Configuring STP
Configuring Basic STP Features
Configuring Basic STP Features
These sections include basic STP configuration information:
• Default STP Configuration, page 10-21
• Disabling STP, page 10-22
• Configuring the Root Switch, page 10-22
• Configuring a Secondary Root Switch, page 10-24
• Configuring STP Port Priority, page 10-26
• Configuring STP Path Cost, page 10-27
• Configuring the Switch Priority of a VLAN, page 10-28
• Configuring the Hello Time, page 10-29
• Configuring the Forwarding-Delay Time for a VLAN, page 10-29
• Configuring the Maximum-Aging Time for a VLAN, page 10-30
• Configuring STP for Use in a Cascaded Stack, page 10-30
• Displaying STP Status, page 10-31
For advanced configuration information, see the “Configuring Advanced STP Features” section on
page 10-32.
Default STP Configuration
Table 10-3 shows the default STP configuration.
Table 10-3 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 Layer 2 access ports)
128.
Spanning-tree port cost (configurable on a per-interface basis—used on
interfaces configured as Layer 2 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 Layer 2 trunk ports)
128.
Spanning-tree VLAN port cost (configurable on a per-VLAN basis—used on
interfaces configured as Layer 2 trunk ports)
1000 Mbps: 4.
100 Mbps: 19.
10 Mbps: 100.
Hello time 2 seconds.
