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● If a BPDU is received from a remote device, BPDU guard places the port in an Err-Disabled Blocking
state and no traffic is forwarded on the port.
● If no BPDU is received from a remote device, loop guard places the port in a Loop-Inconsistent
Blocking state and no traffic is forwarded on the port.
Example
Dell(conf)#interface gigabitethernet 4/0
Dell(conf-if-gi-4/0)#spanning-tree rstp edge-port
Dell(conf-if-gi-4/0)#show config
!
interface GigabitEthernet 4/0
no ip address
switchport
spanning-tree rstp edge-port
no shutdown
Dell#
spanning-tree rstp
Configure 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 configure 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.
bpdufilter (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 configured.
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.
Rapid Spanning Tree Protocol (RSTP) 1005