Allied Telesis AT-IE510-28GSX-80, Руководство по установке

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Chapter 11: Troubleshooting
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not form the stack if the cables or transceivers are from another
vendor.

Verify that VCStack is activated on the switches. For instructions,
refer to Chapter 8, “Verifying the Status of VCStack” on page 89.

It could be that the switches have incompatible versions of the
management software. When a stack forms or a new switch is
added to an existing stack, the master switch downloads its
management software to member switches that do not have the
same version. If the master switch encounters a problem
downloading the management software to a member switch, it
does not allow the device to join the stack.
Problem 4: The LINK/ACT LED for an SFP or SFP+ 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 SFP or SFP+ module and to the port on the remote network
device.

Check that the transceiver is fully inserted in the slot.

If you are using SFP+ slots 27 or 28, check that the VCStack
feature is disabled on the switch. The VCStack feature has to be
disabled before you can use the slots with regular SFP or SFP+
transceivers. For instructions, refer to “Disabling VCStack” on
page 83.

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.
This is to eliminate the possibility that the port is connected to the
wrong remote network 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 managed device, use its
management firmware to determine whether its port is enabled.

Test the attenuation of both directions 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).