Rapid Spanning Tree Protocol (RSTP) | 469To change the port cost or priority of an interface, use the following commands:To view the current values for interface parameters, use the show spanning-tree rstp command from EXECprivilege mode (Figure 27-5).Configure an EdgePortThe EdgePort feature enables interfaces to begin forwarding traffic approximately 30 seconds sooner. Inthis mode, an interface forwards frames by default until it receives a BPDU that indicates that it shouldbehave otherwise; it does not go through the Learning and Listening states. The bpduguardshutdown-on-violation option causes the interface hardware to be shutdown when it receives a BPDU. Whenyou implement only bpduguard, although the interface is placed in an Error Disabled state when receivingthe BPDU, the physical interface remains up and spanning-tree drops packets in the hardware after aBPDU violation. BPDUs are dropped in the software after receiving the BPDU violation. This feature isthe same as PortFast mode in Spanning Tree.Enabling BPDU Filtering on an interface, stops sending and receiving of BPDUs on the port fast enabledports. When BPDU guard and BPDU filter is enabled on the port, BPDU filter takes the highestprecedence. By default bpdu filtering on an interface is disabled.To enable EdgePort on an interface, use the following command:To verify that EdgePort is enabled on a port, use the show spanning-tree rstp command from EXEC privilegemode or the show config command from INTERFACE mode. Dell Force10 recommends using the showconfig command (Figure 27-8).Task Command Syntax Command ModeChange the port cost of an interface.Range: 0 to 65535Default: refer to Table 27-2.spanning-tree rstp cost cost INTERFACEChange the port priority of an interface.Range: 0 to 240Default: 128spanning-tree rstp priority priority-value INTERFACECaution: Configure EdgePort only on links connecting to an end station. EdgePort can cause loops if you enable iton an interface connected to a network.Task Command Syntax Command ModeEnable EdgePort on an interface. spanning-tree rstp edge-port [bpduguard[shutdown-on-violation] | bpdufilter]INTERFACE
