Connectivity Guide

RSTP is single instance and hence MAC flush optimization is not required. However, to enable this feature, configure the
MAC flush timer to a non-zero value. This configuration is applied globally and applies for RSTP, MSTP, and RPVST. This
configuration is retained when you change the STP mode.
For RSTP, the threshold is set to a higher value (65,535) because RSTP does not require this optimization. Even when this
feature is enabled, the global flush is invoked only after the flush count reaches 65,535.
RSTP commands
clear spanning-tree counters
Clears the counters for STP.
Syntax
clear spanning-tree counters [interface {ethernet node/slot/port[:subport]
| port—channel number}}]
Parameters
● interface — Enter the interface type:
○ ethernet node/slot/port[:subport] — Deletes the spanning-tree counters from a
physical port.
○ port-channel number — Deletes the spanning-tree counters for a port-channel interface,
from 1 to 128.
Default Not configured
Command Mode EXEC
Usage
Information
Clear all STP counters on the device per the Ethernet interface or port-channel.
Example
OS10# clear spanning-tree counters interface port-channel 10
Supported
Releases
10.2.0E or later
show spanning-tree active
Displays the RSTP configuration and information for RSTP-active interfaces.
Syntax
show spanning-tree active
Parameters None
Default Not configured
Command Mode EXEC
Usage
Information
None
Example
OS10# show spanning-tree active
Spanning tree enabled protocol rstp with force-version rstp
Executing IEEE compatible Spanning Tree Protocol
Root ID Priority 32768, Address 90b1.1cf4.9b8a
Root Bridge hello time 2, max age 20, forward delay 15
Bridge ID Priority 32768, Address 90b1.1cf4.9b8a
We are the root
Configured hello time 2, max age 20, forward delay 15
Interface Designated
Name PortID Prio Cost Sts Cost Bridge ID PortID
----------------------------------------------------------------------
ethernet1/1/1 244.128 128 500 BLK 0 32768 90b1.1cf4.9b8a 128.244
ethernet1/1/2 248.128 128 500 BLK 0 32768 90b1.1cf4.9b8a 128.248
ethernet1/1/3 252.128 128 500 FWD 0 32768 90b1.1cf4.9b8a 128.252
ethernet1/1/4 256.128 128 500 BLK 0 32768 90b1.1cf4.9b8a 128.256
346 Layer 2