H3C Technologies H3C WX5500E Series Access Controllers - Manual (Page 24)

13
Testing the cable connection of an Ethernet interface
IMPORTANT:
•
Fiber ports do not support this feature.
• If the link of an Ethernet port is up, testing its cable connection will cause the link to come down and then
go up.
You can test the cable connection of an Ethernet interface for a short or open circuit. The device displays
cable test results within five seconds. If any fault is detected, the test results include the length of the faulty
cable segment.
To test the cable connection of an Ethernet interface:
Step Command
1. Enter system view. system-view
2. Enter Ethernet interface view. interface interface-type interface-number
3. Test the cable connected to the Ethernet interface. virtual-cable-test
Configuring storm control on an Ethernet interface
Storm control compares broadcast, multicast, and unknown unicast traffic regularly with their respective
traffic thresholds on an Ethernet interface. For each type of traffic, storm control provides a lower
threshold and a higher threshold.
For management purposes, you can configure the interface to send threshold event traps and log
messages when monitored traffic exceeds the upper threshold or falls below the lower threshold from the
upper threshold.
Depending on your configuration, when a particular type of traffic exceeds its upper threshold, the
interface does either of the following:
• Blocks this type of traffic, while forwarding other types of traffic. Even though the interface does not
forward the blocked traffic, it still counts the traffic. When the blocked traffic drops below the lower
threshold, the port begins to forward the traffic.
• Shuts down automatically. The interface shuts down automatically and stops forwarding any traffic.
When the blocked traffic is detected dropping below the lower threshold, the port does not forward
the traffic. To bring up the interface, use the undo shutdown command or disable the storm control
function.
Alternatively, you can configure the storm suppression function to control a specific type of traffic. Do not
enable them both on an Ethernet interface at the same time because the storm suppression and storm
control functions are mutually exclusive. For example, with an unknown unicast suppression threshold set
on an Ethernet interface, do not enable storm control for unknown unicast traffic on the interface. For
more information about storm suppression, see " Configuring storm suppression ."
Configuration guidelines
• For network stability, use the default or set a higher traffic polling interval.
• Storm control uses a complete polling cycle to collect traffic data, and analyzes the data in the next
cycle. An interface takes one to two polling intervals to take a storm control action.