• 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 126. Enabling BPDU GuardDell Networking OS Behavior: BPDU guard and BPDU filtering both block BPDUs, but are two separate features.BPDU guard:• is used on edgeports and blocks all traffic on edgeport if it receives a BPDU.• drops the BPDU after it reaches the RP and generates a console message.BPDU filtering:• disables spanning tree on an interface• drops all BPDUs at the line card without generating a console messageExample of Blocked BPDUsDell(conf-if-te-1/7)#do show spanning-tree rstp briefExecuting IEEE compatible Spanning Tree ProtocolRoot ID Priority 32768, Address 0001.e805.fb07Root Bridge hello time 2, max age 20, forward delay 15Bridge ID Priority 32768, Address 0001.e85d.0e90Configured hello time 2, max age 20, forward delay 15Interface DesignatedName PortID Prio Cost Sts Cost Bridge ID PortID---------- -------- ---- ------- --- ------- --------------------Te 1/6 128.263 128 20000 FWD 20000 32768 0001.e805.fb07 128.653Te 1/7 128.264 128 20000 EDS 20000 32768 0001.e85d.0e90 128.264InterfaceName Role PortID Prio Cost Sts Cost Link-type Edge930 Spanning Tree Protocol (STP)
