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● 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]
To verify that EdgePort is enabled on a port, use the show spanning-tree rstp command from EXEC privilege mode or
the show config command from INTERFACE mode.
NOTE: Dell Networking recommends using the show config command from INTERFACE mode.
In the following example, the bold line indicates that the interface is in EdgePort mode.
Dell(conf-if-Te-2/0)#show config
!
interface TenGigabitEthernet 2/0
no ip address
switchport
spanning-tree rstp edge-port
shutdown
Dell(conf-if-Te-2/0)#
Influencing RSTP Root Selection
RSTP determines the root bridge, but you can assign one bridge a lower priority to increase the likelihood that it is selected as
the root bridge.
To change the bridge priority, use the following command.
● Assign a number as the bridge priority or designate it as the primary or secondary root.
PROTOCOL SPANNING TREE RSTP mode
bridge-priority priority-value
○ priority-value The range is from 0 to 65535. The lower the number assigned, the more likely this bridge becomes
the root bridge.
The default is 32768. Entries must be multiples of 4096.
A console message appears when a new root bridge has been assigned. The following example shows the console message after
the bridge-priority command is used to make R2 the root bridge (shown in bold).
Dell(conf-rstp)#bridge-priority 4096
04:27:59: %RPM0-P:RP2 %SPANMGR-5-STP_ROOT_CHANGE: RSTP root changed. My Bridge ID:
4096:0001.e80b.88bd Old Root: 32768:0001.e801.cbb4 New Root: 4096:0001.e80b.88bd
Enabling SNMP Traps for Root Elections and Topology Changes
To enable SNMP traps collectively, use this command.
Enable SNMP traps for RSTP, MSTP, and PVST+ collectively.
snmp-server enable traps xstp
Rapid Spanning Tree Protocol (RSTP)
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