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Storm Control Configuration
Table 38. Storm Control Configuration Fields
Click
Apply
to save the changes for the current boot session. The changes take effect immediately but
are not retained across a switch reset unless you click
Save Configuration
.
Field
Description
Storm Control Features
Storm Control
Storm control enables the rate-limiting of incoming unicast (with unknown destination),
multicast, and broadcast traffic to prevent unnecessary congestion in the network. When
enabled, the storm control threshold is automatically set to 5% of port speed. If the incoming
rate of unicast (with unknown destination), multicast, or broadcast packets exceeds this
value, the port moves to the diagnostically disabled state and remains in that state until it is
re-enabled by the Auto recovery feature. Storm Control functionality is applicable only for
physical interfaces. This feature is disabled by default.
Note
: The threshold percentage is translated to a packets-per-second value that is used by
the switch hardware to rate-limit the incoming traffic. This translation assumes a nominal 512
byte packet size to determine the packets-per-second threshold based on the port speed. For
example, the 5% threshold applied to a 1 Gbps port equates to approximately 11748 packets-
per-second, regardless of the actual packet sizes being received by the port. Each of the
three storm control packet types is rate-limited independently.
Auto Recovery Parameters
Auto Recovery
This configures the Storm Control auto recovery administrative mode. This feature is disabled
by default.
Recovery Time
This configures the Storm Control auto recovery time interval. The default value of the timer
is 300 seconds and the range is from 30 to 86400.
Interface Status
Interface
The interface which is diagnostically disabled. This table displays only those interfaces that
have been placed in a diagnostically disabled state due to the detection of a broadcast storm.
Admin Mode
The administrative mode of the interface.
Port Status
Indicates whether the link is up or down. The link is the physical connection between the port
or trunk and the interface on another device.
Reason
If the switch detects an error condition for an interface due to a broadcast storm, then the
switch puts the interface in the diagnostically disabled state. The reason that the interface can
go into the diagnostically disabled state is the following:
Storm Control
Time to Recover
When Auto Recovery is enabled and the interface is placed in diagnostically disabled state,
then a recovery timer starts for that interface. Once this timer expires, the device checks if the
interface is in the diagnostically disabled state. If yes, then the device enables the
diagnostically disabled interface.