Common problems, Link/receive led on any port is off, Common problems -5 – Allied Telesis AT-8126XL User Manual
Page 39: Link/receive led on any port is off -5
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AT-8118, AT-8124XL, and AT-8126XL Installation Guide
3-5
Common Problems
This section lists common possible sources of error and actions
required to fix them.
Link/Receive
LED on Any Port
is OFF
This may indicate:
" A loose data cable.
" The device at the other end of the connection is turned OFF.
" The data cable is not wired correctly (straight/crossed) for the
device.
" The nework administrator manually disabled the port through
the software.
" The port’s selected transmission mode does not match that of
the attached device.
Perform the following steps in sequence; you need not proceed to
the next step if the problem is resolved:
1. Make sure the data cables are secure.
2. Make sure the device at the end of the connection is turned ON.
3. Make sure the data cable is wired correctly (straight/crossed) for
the device.
4. Logon to Omega if you can and check the port status (
Port
status and configuration><port number>
menu).
If the port is Enabled, make sure the transmission speed
matches that of the connected device (auto-negotiating, full-
or half-duplex).
Refer to the AT-S21 Software Management User’s Guide to
check that the port is
Disabled
. If the port is
Disabled
,
someone has manually disabled the port through the
software for a specific reason. Verify that the reason no longer
exists before you enable this port (
Port status and
configuration
).
5. Contact Allied Telesyn’s Technical Support for help.