Users Guide

2. In CONFIGURATION mode, use the following command to recover the ports from shutting down due to the detection of a
BPDU Guard violation. When the recovery option is enabled, the port is brought up after the recovery timer expires. The
default recovery timer value is 300 seconds. When the recovery option is disabled, the port remains shut down indefinitely.
You must manually bring up the port using the shutdown and no shutdown commands.
errdisable recovery cause bpduguard
The no version of the command disables the recovery option.
3. To change the recover timer value, use the following command in CONFIGURATION mode. This recovery timer value is
applicable only for shutdown case. For Blocking case, the default value of 300 seconds is used.
errdisable recovery interval interval-value
Example configuration
OS10(config)# errdisable detect cause bpduguard
OS10(config)# errdisable recovery interval 45
OS10(config)# errdisable recovery cause bpduguard
View detect and recovery details
OS10# show errdisable detect
Error-Disable Cause Detect Status
-----------------------------------------------
bpduguard Enabled
OS10# show errdisable recovery
Error-Disable Recovery Timer Interval: 300 seconds
Error-Disable Reason Recovery Status
---------------------------------------------------
bpduguard Enabled
Recovery Time left
Interface Errdisable Cause (seconds)
---------------------------------------------------------------------
ethernet 1/1/1:1 bpduguard 273
ethernet 1/1/2 bpduguard 4
port-channel 12 bpduguard 45
MAC flush optimization
OS10 offers a MAC address clearing technique that optimizes the number of MAC flush calls sent by the Spanning Tree Protocol
(STP) module.
If the number of calls sent to the hardware is too high, traffic is dropped or flooded impacting system performance. To prevent
traffic drops and flooding, you can use the MAC flush optimization feature.
This feature fine-tunes the MAC flush-related parameters, such as the MAC flush threshold and the MAC flush timer to reduce
the number of calls sent to the hardware. The clear request sent to clear the MAC address table entry is called a flush
indication. The number of calls that are sent is displayed as flush invocations in the show spanning-tree command.
You can enable the MAC flush optimization feature by setting the MAC flush timer to a non-zero value. This feature is enabled
by default with a default timer value of 200 centi-seconds.
To disable MAC flush optimization, configure the MAC flush timer value to 0.
When you configure the MAC flush timer to a non-zero value and the threshold to zero, the system invokes instance-based
flush once and starts the timer. When the timer expires, the system invokes an instance-based flush again.
The show spanning-tree {brief | details | active} command displays the following information:
Flush Interval 200 centi-sec, Flush Invocations 32
Flush Indication threshold 2
Layer 2
597