DGS-3710 Series Layer 2 Managed Gigabit Switch CLI Reference Guide
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Chapter 11
Cable Diagnostics
Commands
cable_diag ports
[<portlist> | all]
11-1
cable_diag ports
Description
This command is used to test copper cabling. For 1000Base-T link speed RJ45 cable, four pairs of
cable will be diagnosed. The type of cable errors can be open, short, or crosstalk. Open means
that the cable in the error pair does not have a connection at the specified position, short means
that the cables in the error pair has a short problem at the specified position, and crosstalk means
that the cable in the error pair has a crosstalk problem at the specified position.
When a port is in link-up status, the test will obtain the distance of the cable. Since the status is
link-up, the cable will not have the short or open problem. The test may still detect the crosstalk
problem, however.
When a port is in link-down status, the link-down may be caused by many factors.
When the port has a normal cable connection, but the remote partner is powered off, the cable
diagnosis can still diagnose the health of the cable as if the remote partner is powered on. When
the port does not have any cable connection, the result of the test will indicate no cable. The test
will detect the type of error and the position where the error occurs.
Note:
This test will consume a low number of packets. Since this test is for copper
cable, the port with fiber cable will be skipped from the test.
Format
cable_diag ports [<portlist> | all]
Parameters
<portlist>
- Specifies a range of ports to be configured.
all
– Specifies to set all ports in the system.
Restrictions
Only Administrator-level users can issue this command.
Example
To test the cable on ports 1 to 4, and 8: