Spanning Tree
59
Auto Recovery Configuration
The switch supports Auto Recovery for BPDU Guard, BPDU Rate Limiting, and Storm Control. A
switch port will be placed into a diagnostically disabled state when defined error conditions are met.
The error conditions that cause a port to be placed into the diagnostically disabled state are as follows:
BPDU Guard: If a port that has the BPDU Guard feature enabled receives a BPDU, it is placed in
the diagnostically disabled state.
BPDU Rate Limit: When Spanning Tree is enabled, BPDU Rate Limiting is enabled by default to
protect the switch from BPDU storms. The BPDU rate limit threshold is set to 12–17 BPDU pack-
ets per second for three consecutive seconds.
When a port has been placed into a diagnostically disabled state, the port is shutdown, and no traffic is
sent or received on the port until it is either manually enabled by the administrator or re-enabled by the
Auto Recovery feature.
The Auto Recovery feature will automatically re-enable a diagnostically disabled port when the error
conditions that caused the port to be disabled are no longer detected. The switch utilizes a configu-
rable Auto Recovery timer to periodically check the error condition at set intervals. If the error condition
is no longer present, the port will be re-enabled. The administrator can manually override the timer set-
ting by re-enabling a port at any time.
Auto Recovery is disabled by default. When disabled, ports in a diagnostically disabled state remain
disabled until an administrator manually enables them.
Use the Auto Recovery Configuration page to configure Auto Recovery settings for STP BPDU Guard
and BPDU Rate Limit components. To display this page, click
Switching
>
Spanning Tree
in the nav-
igation pane, and then click the
Auto Recovery
tab.
Figure 33.
Auto Recovery Configuration Page
