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Catalyst 6500 Series Switch Cisco IOS Software Configuration Guide—Release 12.1 E
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Chapter 15 Configuring STP and IEEE 802.1s MST
Default STP Configuration
Default STP Configuration
Table 15-5 shows the default STP configuration.
STP and MST Configuration Guidelines
Follow these guidelines when configuring MST:
Do not disable spanning tree on any VLAN in any of the PVST bridges.
Do not use PVST bridges as the root of CST.
Ensure that all PVST spanning tree root bridges have lower (numerically higher) priority than the
CST root bridge.
Table 15-5 STP Default Configuration
Feature Default Value
Enable state STP enabled for all VLANs
Bridge priority 32768
STP port priority (configurable on a per-port
basis—used on LAN ports configured as
Layer 2 access ports)
128
STP port cost (configurable on a per-port
basis—used on LAN ports configured as
Layer 2 access ports)
10-Gigabit Ethernet: 2
Gigabit Ethernet: 4
Fast Ethernet: 19
Ethernet: 100
STP VLAN port priority (configurable on a
per-VLAN basis—used on LAN ports
configured as Layer 2 trunk ports)
128
STP VLAN port cost (configurable on a
per-VLAN basis—used on LAN ports
configured as Layer 2 trunk ports)
10-Gigabit Ethernet: 2
Gigabit Ethernet: 4
Fast Ethernet: 19
Ethernet: 100
Hello time 2 seconds
Forward delay time 15 seconds
Maximum aging time 20 seconds
Mode PVST