Dell C1048P Port Extender Networking Configuration Guide for the C9000 Series - Page 788

NOTE: The Dell Networking OS implementation of PVST+ uses IEEE 802.1s costs as the default costs. Other implementations use IEEE 802.1w costs as the default costs. If you are using Dell Networking systems in a multi-vendor network, verify that the costs are values you intended. To change the port cost or port priority of an interface, use the following commands. • Change the port cost of an interface. INTERFACE mode spanning-tree pvst vlan cost. The range is from 0 to 200000. Refer to the table for the default values. • Change the port priority of an interface. INTERFACE mode spanning-tree pvst vlan priority. The range is from 0 to 240, in increments of 16. The default is 128. The values for interface PVST+ parameters are given in the output of the show spanning-tree pvst command, as previously shown. Configuring an EdgePort The EdgePort feature enables interfaces to begin forwarding traffic approximately 30 seconds sooner. In this mode an interface forwards frames by default until it receives a BPDU that indicates that it should behave otherwise; it does not go through the Learning and Listening states. The bpduguard shutdown-onviolation option causes the interface hardware to be shut down when it receives a BPDU. When you only implement bpduguard, although the interface is placed in an Error Disabled state when receiving the BPDU, the physical interface remains up and spanning-tree drops packets in the hardware after a BPDU violation. BPDUs are dropped in the software after receiving the BPDU violation. This feature is the same as PortFast mode in spanning tree. CAUTION: Configure EdgePort only on links connecting to an end station. EdgePort can cause loops if you enable it on an interface connected to a network. To enable EdgePort on an interface, use the following command. • Enable EdgePort on an interface. INTERFACE mode spanning-tree pvst edge-port [bpduguard | shutdown-on-violation] The EdgePort status of each interface is given in the output of the show spanning-tree pvst command, as previously shown. Dell Networking OS Behavior: Regarding the bpduguard shutdown-on-violation command behavior: • If the interface to be shut down is a port channel, all the member ports are disabled in the hardware. Per-VLAN Spanning Tree Plus (PVST+) 788