Users Guide

To change the port cost or priority of an interface, use the following commands.
• Change the port cost of an interface.
INTERFACE mode
spanning-tree rstp cost cost
The range is from 0 to 65535.
The default is listed in the previous table.
• Change the port priority of an interface.
INTERFACE mode
spanning-tree rstp priority priority-value
The range is from 0 to 15.
The default is 128.
To view the current values for interface parameters, use the show spanning-tree rstp command from EXEC privilege mode.
Conguring an EdgePort
The EdgePort feature enables interfaces to begin forwarding trac 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-on-violation option causes the interface
hardware to shut down when it receives a BPDU. When only bpduguard is implemented, 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: Congure EdgePort only on links connecting to an end station. If you enable EdgePort on an interface
connected to a network, it can cause loops.
Dell Networking OS Behavior: Regarding bpduguard shutdown-on-violation behavior:
• If the interface to 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 stack-unit 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 an 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).
– Disable global spanning tree (the no spanning-tree command in CONFIGURATION mode).
To enable EdgePort on an interface, use the following command.
• Enable EdgePort on an interface.
INTERFACE mode
spanning-tree rstp edge-port [bpduguard | shutdown-on-violation]
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Rapid Spanning Tree Protocol (RSTP)