Dell C1048P Port Extender Networking Configuration Guide for the C9000 Series - Page 1000

• 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). • The reset linecard command does not clear the Error Disabled state of the port or the Hardware Disabled state. The interface continues to be disables 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 127. Enabling BPDU Guard Dell 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 Route Processor and generates a console message. BPDU filtering: 1000 Spanning Tree Protocol (STP)