Allied Telesis AT-S47 - Manual (Page 56)

Section II: Menu Interface
56
Overview
The Link Test feature is a fast and easy way for you to test the link
integrity between local and remote multiplexing ports. The test is
usually performed during pre-installation, while there is no real traffic on
the ports.
Below are guidelines to observe when performing a Link Test:
❑ You can test the multiplexing ports on an AT-WD1008
independently of each other.
❑ Both the corresponding local and remote multiplexing ports must
be in the Link Test mode for the test to work properly. For
instance, to perform a Link Test on a local WEST (OPT A)
multiplexing port, you must set the remote EAST (OPT B)
multiplexing port also in Link Test mode.
❑ The test sends a test pattern over the fiber strand. It checks the
integrity of the strand, not the multiplexing capability of the ports.
❑ The WEST (OPT A) multiplexing port, when in Link Test mode, will
not forward traffic from the GBIC module in the CH1 slot. The GBIC
modules in CH2 to CH4 are not affected by a Link Test.
❑ The EAST (OPT B) multiplexing port, when in Link Test mode, will
not forward traffic from the GBIC module in the CH5 slot. The GBIC
modules in CH6 to CH8 are not affected by a Link Test.
To view the results of a Link Test, you can check the TX and RX LEDs on
the multiplexing ports. They should be solid green.
You can also view the Module Status Menu. A multiplexing port that has
successfully established a link with its corresponding remote port will be
showing “Online” in the Tx/Status and Rx columns.
If the multiplexing ports are unable to establish a link, try resolving the
problem by doing the following:
❑ Verify that both multiplexers are powered ON.
❑ Verify that the multiplexing ports on both multiplexers are in Link
Test mode.
❑ Check that the fiber optic cable is securely connected to the
multiplexing ports.
❑ Verify that the cables between the multiplexing ports cross. The
WEST (OPT A) port must be connected to the EAST (OPT B) port,
and the EAST (OPT B) port connected to the WEST (OPT A) port. Do
not connect two WEST (OPT A) ports or two EAST (OPT B) ports
together.