Concept Guide
• You can clear the Error Disabled state with any of the following methods:
– Perform a shutdown command on the interface.
– Disable the shutdown-on-violation command on the interface (the no spanning-tree stp-id portfast
[bpduguard | [shutdown-on-violation]] command).
– Disable spanning tree on the interface (the no spanning-tree command in INTERFACE mode).
– Disabling global spanning tree (the no spanning-tree in CONFIGURATION mode).
Figure 120. Enabling BPDU Guard
Dell Networking OS Behavior: BPDU guard and BPDU ltering (refer to Removing an Interface from the Spanning Tree Group) both block
BPDUs, but are two separate features.
BPDU guard is used on edgeports and blocks all trac on edgeport if it receives a BPDU.
Example of Blocked BPDUs
Dell#show spanning-tree 0 brief
Executing IEEE compatible Spanning Tree Protocol
Root ID Priority 32768, Address 0001.e88a.fdb3 Cost 1
Root Port 2 (Port-channel 1)
Root Bridge hello time 2, max age 20, forward delay 15
Bridge ID Priority 32768, Address 001e.c9f1.00cf
Configured hello time 2, max age 20, forward delay 15
Bpdu filter disabled globally
Interface Designated
Name PortID Prio Cost Sts Cost Bridge ID PortID
---------- ------- ---- ------ ----------- ------ ------ ------
Po 1 8.2 8 1 FWD 0 32768 0001.e88a.fdb3 8.2
Te 3/20 8.317 8 4 EDS 1 32768 001e.c9f1.00cf 8.317
Te 4/20 8.373 8 4 FWD 1 32768 001e.c9f1.00cf 8.373
Te 4/21 8.374 8 4 FWD 1 32768 001e.c9f1.00cf 8.374
Dell#show ip int br ten 3/20
Interface IP-Address OK Method Status Protocol
846
Spanning Tree Protocol (STP)