Allied Telesis x530 Series Installation Manual page 118

Chapter 9: Troubleshooting
118
Problem 3: A twisted pair port on the AT-x530-28GTXm or AT-x530-
28GPXm switch is connected to an active network device but the port's
LINK/ACT LED is off.
Solutions: The port is unable to establish a link to a network device. Try
the following:
Verify that the network device connected to the twisted pair port is

powered on and is operating properly.
Try connecting another network device to the twisted pair port with

a different cable. If the twisted pair port is able to establish a link,
then the problem is with the cable or the other network device.
Verify that the twisted pair cable does not exceed 100 meters

(328 feet).
Verify that you are using the appropriate category of twisted pair

cable. Refer to Table 4 on page 24.
Verify that the port is connected to the correct twisted pair cable.

Note
Twisted pair ports may require five to ten seconds to establish a link.
Problem 4: The LINK/ACT LED for an SFP, SFP+, or QSFP+ transceiver
is off.
Solutions: The fiber optic port on the transceiver is unable to establish a
link to a network device. Try the following:
Verify that the remote network device connected to the fiber optic

port is operating properly.
Verify that the fiber optic cable is securely connected to the port on

the transceiver and to the port on the remote network device.
Check that the transceiver is fully inserted in the slot.

Verify that the operating specifications of the fiber optic ports on

the transceiver and remote network device are compatible.
Verify that the correct type of fiber optic cabling is being used.

Verify that the port is connected to the correct fiber optic cable.

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 with the other network device.