Concept Guide

spanning-tree rstp
Congure an RSTP interface with one of these settings: port cost, edge port with optional bridge port data unit (BPDU) guard, port
priority, loop guard, or root guard.
Syntax
spanning-tree rstp {cost port-cost | edge-port [bpduguard [shutdown-on-
violation]] | bpdufilter | priority priority | {rootguard}}
Parameters
cost port-cost Enter the keyword cost then the port cost value. The range is from 1 to 200000. The
defaults are:
• 10-Gigabit Ethernet interface = 2000
• Port Channel interface with one 10 Gigabit Ethernet = 2000
• Port Channel interface with one 40 Gigabit Ethernet = 1400
• Port Channel with two 10 Gigabit Ethernet = 1800
• Port Channel with two 40 Gigabit Ethernet = 600
edge-port Enter the keywords edge-port to congure the interface as a rapid spanning tree edge
port.
bpduguard
(OPTIONAL) Enter the keyword portfast to enable Portfast to move the interface into
Forwarding mode immediately after the root fails.
Enter the keyword bpduguard to disable the port when it receives a BPDU.
shutdown-on-
violation
(OPTIONAL) Enter the keywords shutdown-on-violation to hardware disable an
interface when a BPDU is received and the port is disabled.
bpdulter (OPTIONAL) Enter the keyword bpdufilter to enable BPDU Filter to stop sending and
receiving BPDUs on port enabled interfaces.
priority priority Enter keyword priority then a value in increments of 16 as the priority. The range is
from 0 to 240. The default is 128.
rootguard Enter the keyword rootguard to enable root guard on an RSTP port or port-channel
interface.
Defaults Not congured.
Command Modes INTERFACE
Supported Modes Full–Switch
Command History
Version Description
9.9(0.0) Introduced on the FN IOM.
8.3.16.1 Introduced on the MXL 10/40GbE Switch IO Module.
Usage Information
The BPDU guard option prevents the port from participating in an active STP topology in case a BPDU appears
on a port unintentionally, or is miscongured, or is subject to a DOS attack. This option places the port into an Error
Disable state if a BPDU appears and a message is logged so that the administrator can take corrective action.
Rapid Spanning Tree Protocol (RSTP) 1143