xStack DES-3800 Series Layer 3 Stackable Fast Ethernet Managed Switch
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Traffic Control Settings
Storm Type
Select the type of Storm Type to detect, either Broadcast Multicast or Unicast. Once selected, use
the pull-down menu to enable or disable the specified type of storm detection.
Action
Select the method of traffic Control from the pull down menu. The choices are:
Drop – Utilizes the hardware Traffic Control mechanism, which means the Switch’s hardware will
determine the Packet Storm based on the Threshold value stated and drop packets until the issue
is resolved.
Shutdown – Utilizes the Switch’s software Traffic Control mechanism to determine the Packet
Storm occurring. Once detected, the port will deny all incoming traffic to the port except STP BPDU
packets, which are essential in keeping the Spanning Tree operational on the Switch. If the
Countdown timer has expired and yet the Packet Storm continues, the port will be placed in
Shutdown Forever mode and is no longer operational until the user manually resets the port using
the Port Configuration window in the Administration folder and selecting the disabled port and
returning it to an Enabled status. Choosing this option obligates the user to configure the Interval
setting as well, which will provide packet count samplings from the Switch’s chip to determine if a
Packet Storm is occurring.
Port List
Use the From and To drop-down menus to select the ports that need to be manually recovered
from the Shutdown state.
Threshold
(pps)
Specifies the maximum number of packets per second that will trigger the Traffic Control function to
commence. The configurable threshold range is from 0-255000 with a default setting of 128000.
Time Interval
The Interval will set the time between Multicast and Broadcast packet counts sent from the Switch’s
chip to the Traffic Control function. These packet counts are the determining factor in deciding
when incoming packets exceed the Threshold value. The Interval may be set between 5 and 30
seconds with the default setting of 5 seconds.
Countdown
The Countdown timer is set to determine the amount of time, in minutes, that the Switch will wait
before shutting down the port that is experiencing a traffic storm. This parameter is only useful for
ports configured as Shutdown in their Action field and therefore will not operate for Hardware
based Traffic Control implementations. The possible time settings for this field are 0, 5-30 minutes.
0 is the default setting for this field and 0 will denote that the port will immediately shutdown.
Click Apply to implement the settings made.
NOTE: Traffic Control cannot be implemented on ports that are set for
Link Aggregation (Port Trunking).
NOTE: Ports that are in the Shutdown forever mode will be seen as
Discarding in Spanning Tree windows and implementations though these
ports will still be forwarding BPDUs to the Switch’s CPU.
NOTE: Ports that are in Shutdown Forever mode will be seen as link down
in all windows and screens until the user recovers these ports.
