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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
