Dell PowerSwitch S4112F-ON EMC SmartFabric OS10 User Guide Release 10.5.0 - Page 456

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 2 456 Layer 2