Step 3: Locate an Incoming Yellow Alarm
Purpose
An incoming yellow alarm indicates that the T3 network element connected to the T3 interface has a problem with the signal it is receiving from the T3 interface.
Action
To locate the yellow alarm, check the cable between the T3 interface and the directly connected T3 network element.
All diagnostics are from the perspective of Router2. Figure 8 illustrates the location of a yellow alarm in a T3 network.
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What It Means
The T3 multiplexer detects an LOS or LOF on its connection from Router2 and sends a yellow (YLW) alarm to Router2.