Administrator Guide

Dell Networking OS Behavior: Regarding bpduguard shutdown-on-violation behavior:
• If the interface to be shut down is a port channel, all the member ports are disabled in the hardware.
• When you add a physical port to a port channel already in the Error Disable state, the new member port is also disabled in the
hardware.
• When you remove a physical port from a port channel in the Error Disable state, the Error Disabled state is cleared on this
physical port (the physical port is enabled in the hardware).
• 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 125. 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 trac 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
Spanning Tree Protocol (STP)
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