3Com Switch 4800G 24-Port Configuration Manual page 154

154 C 16: P C
HAPTER ORT
n
Testing the Cable on an
Ethernet Port
n
C
ORRELATION ONFIGURATION
Ethernet interface on a device can operate in one of the following three Medium
Dependent Interface (MDI) modes:
Across mode, where the Ethernet interface only accepts crossover cables.
■
Normal mode, where the Ethernet interface only accepts straight-through
■
cables.
Auto mode, where the Ethernet interface accepts both straight-through cables
■
and crossover cables.
Normally, the auto mode is recommended. The other two modes are useful only
when the device cannot determine the cable type.
Follow these steps to configure the cable type for an Ethernet Port:
To do...
Enter system view
Enter Ethernet port view
Configure the cable type the
Ethernet port can identify
10 GE port cannot support mdi configuration.
A link in the up state goes down and then up automatically if you perform the
operation described in this section on one of the Ethernet ports forming the link.
You can enable the test on the cable connected with an Ethernet port to check:
Whether the RX and TX of the cable are short-circuited.
■
Whether the cable is open circuited.
■
The length of the faulty cable if there is any fault.
■
The system will return the check result in 5 seconds.
Follow these steps to test the current operating state of the cable connected to an
Ethernet port:
To do...
Enter system view
Enter Ethernet port view
Test the current operating state
of the cable connected to the
port
Use the command...
system-view
interface interface-type
interface-number
mdi { across | auto |
normal }
Use the command...
system-view
interface interface-type
interface-number
virtual-cable-test
Remarks
-
-
Optional
Defaults to auto. That is, the
Ethernet port automatically
detects the type of the cable
in use.
Remarks
-
-
Required