z
external
: Performs external loop test. In the external loop test, self-loop headers must be used on
the port of the switch ( for 100M port, the self-loop headers are made from four cores of the 8-core
cables, for 1000M port, the self-loop header are made from eight cores of the 8-core cables, then
the packets forwarded by the port will be received by itself.). The external loop test can locate the
hardware failures on the port.
z
internal
: Performs internal loop test. In the internal loop test, self loop is established in the
switching chip to locate the chip failure which is related to the port.
Note that:
z
After you use the
shutdown
command on a port, the port cannot run loopback test.
z
You cannot use the
speed
,
duplex
,
mdi
and
shutdown
commands on the ports running loopback
test.
z
Some ports do not support loopback test, and corresponding prompts will be given when you
perform loopback test on them.
Enabling the System to Test Connected Cable
You can enable the system to test the cable connected to a specific port. The test result will be returned
in five seconds. The system can test these attributes of the cable: Receive and transmit directions (RX
and TX), short circuit/open circuit or not, the length of the faulty cable.
Follow these steps to enable the system to test connected cables:
To do...
Use the command...
Remarks
Enter system view
system-view
—
Enter Ethernet port view
interface interface-type
interface-number
—
Enable the system to test
connected cables
virtual-cable-test
Required
Configuring the Interval to Perform Statistical Analysis on Port Traffic
By performing the following configuration, you can set the interval to perform statistical analysis on the
traffic of a port.
When you use the
display interface interface-type interface-number
command to display the
information of a port, the system performs statistical analysis on the traffic flow passing through the port
during the specified interval and displays the average rates in the interval. For example, if you set this
interval to 100 seconds, the displayed information is as follows:
Last 100 seconds input: 0 packets/sec 0 bytes/sec
Last 100 seconds output: 0 packets/sec 0 bytes/sec
Follow these steps to set the interval to perform statistical analysis on port traffic:
To do...
Use the command...
Remarks
Enter system view
system-view
—
12-8
