Users Guide

Root Bridge hello time 2, max age 20, forward delay 15
Bridge ID Priority 32768,
Address 0001.e800.0a56
Configured hello time 2, max age 20, forward delay 15
Interface Designated
Name PortID Prio Cost Sts Cost Bridge ID PortID
-------------- ------ ---- ---- --- ----- ------------------
Gi 1/1 8.26 8 4 FWD 0 32768 0001.e800.0a56 8.26
Gi 1/2 8.27 8 4 FWD 0 32768 0001.e800.0a56 8.27
Gi 1/3 8.28 8 4 FWD 0 32768 0001.e800.0a56 8.28
Dell#
Usage Information The following describes the show spanning-tree 0 guard command shown in the example.
Field Description
Interface Name STP interface.
Instance STP 0 instance.
Sts Port state: root-inconsistent (INCON Root), forwarding (FWD), listening (LIS), blocking
(BLK), or shut down (EDS Shut).
Guard Type Type of STP guard configured (Root, Loop, or BPDU guard).
Example (Guard)
Dell#show spanning-tree 0 guard
Interface
Name Instance Sts Guard type
-------- -------- --------- ----------
Gi 1/1 0 INCON(Root) Rootguard
Gi 1/2 0 LIS Loopguard
Gi 1/3 0 EDS (Shut) Bpduguard
spanning-tree
Assigns a Layer 2 interface to STP instance 0 and configures a port cost or port priority, or enables loop guard, root guard, or the Portfast
feature on the interface.
Syntax
spanning-tree stp-id {cost cost | {loopguard | rootguard} | portfast [bpduguard
[shutdown-on-violation]] | priority priority}
To disable Spanning Tree group on an interface, use the no spanning-tree stp-id {cost cost |
{loopguard | rootguard} | portfast [bpduguard [shutdown-on-violation]] |
priority priority} command.
Parameters
stp-id Enter the STP instance ID. The range is 0.
cost cost Enter the keyword cost then a number as the cost. The range is from 1 to 65535. The
defaults are:
• 1-Gigabit Ethernet interface = 4.
• 10-Gigabit Ethernet interface = 2.
• Port Channel interface with 100 Mb/s Ethernet = 18.
• Port Channel interface with 1 Gigabit Ethernet = 3.
• Port Channel interface with 10 Gigabit Ethernet = 1.
loopguard Enter the keyword loopguard to enable STP loop guard on a port or port-channel
interface.
rootguard Enter the keyword rootguard to enable STP root guard on a port or port-channel
interface.
portfast
[bpduguard
[shutdown-on-viol
ation]]
Enter the keyword portfast to enable Portfast to move the interface into Forwarding
mode immediately after the root fails.
Enter the optional keyword bpduguard to disable the port when it receives a BPDU.
1314 Spanning Tree Protocol (STP)