Allied Telesis GS950 PS Series, Руководство по установке, Страница: 93 / 108

GS950 PS V2 Series of Gigabit PoE+ Ethernet Switches Installation Guide
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SFP Ports
The Link/Activity LED for an SFP transceiver is off, signaling that the fiber
optic port on the transceiver has not established a link to a remote network
device. Try the following:

Verify that the switch supports the transceiver. Refer to “SFP
Ports” on page 29.
 Verify that the remote network device is operating properly.
 Verify that the fiber optic cable is securely connected to the ports
on the switch and remote network device.

Verify that the SFP transceiver is fully inserted in the slot in the
switch.
 Verify that the operating specifications, including wavelength and
operating distance, of the fiber optic ports on the SFP transceiver
and remote network device are compatible. The operating
specifications for the transceivers are included with the modules.

Verify that the correct type of fiber optic cabling is being used.

Verify that the port is connected to the correct fiber optic cable.
This is to confirm that the port is not connected to the wrong
remote network device, such as a powered off device.

Try connecting another network device to the fiber optic port using
a different cable. If the port is able to establish a link, then the
problem is with the cable or other network device.
 Use the switch’s management software to verify that the port is
enabled.
 If the remote network device is a management device, use its
management firmware to verify that its port is enabled.

Test the attenuation on the fiber optic cable with a fiber optic tester
to determine whether the optical signal is too weak (sensitivity) or
too strong (maximum input power).

Check the two strands of the fiber optic cable to be sure that the
receive fiber connector is connected to the transmit connector on
the remote end node, and that the transmit fiber connector is
connected to the receive connector on the end node.
 If the problem is with bi-directional transceivers, refer to their data
sheets to verify that their transmission and reception frequencies
are opposite each other. For instance, a bi-directional transceiver
that transmits and receives at 1310nm and 1550nm, respectively,
has to be connected to a transceiver that transmits and receives at
1550nm and 1310nm, respectively. Two bi-directional transceivers
will not be able to establish a link if they transmit and receive at the
same frequencies.