Specifications

Page 5–12
FOCUS System Manual
which is specified by the user in the FCS APM
> Define dialog box.
5.1.5.2 Detecting the Location and
Probable Cause of Failure
When an APM event occurs, each FOCUS chassis
in the loop logs one or more system events indi-
cating its response to the APM event. Two types of
system events could be recorded at this time:
1. FOCUS System APM Loop 1 Going Down
02/12/97 15:16:13.000 \ Direction: X1_1,
Reason: Adjacent chassis down
2. FOCUS System APM Loop 1 Flipping
02/12/97 15:16:13.000 \
Initiated by: 0907, Direction: X1_2
Note that the time, direction, reason and, “initiated
by” data will vary. Both of these events indicate
where the failure first originated.
To determine the location of the failure which
activated APM, log onto any FOCUS chassis in
the loop via FCS (FOCUS Configuration
Software) and retrieve the current targets (“View
All Targets”). For an APM event, three possible
combinations of the above two events may be
logged. These are:
1. The single event:
“FOCUS System APM Loop 1 Flipping
02/12/97 15:16:13.000 \
Initiated by: 0907, Direction: X1_2”
This indicates that the failure is not adjacent
to this chassis. The target gives the time the
event occurred and the FOCUS chassis that
initiated APM (i.e., found a problem) and the
direction of the failure with respect to the
initiator.
2. The single event:
“FOCUS System APM Loop 1 Going Down
02/12/97 15:16:13.000 \ Direction: X1_1,
Reason: Adjacent chassis down”
This indicates that a failure was adjacent to
this chassis in the indicated direction (in this
case on XCVR 1-1).
3. Two events, one immediately following the
other:
“
APM Loop 1 Going Down…Reason:
Adjacent chassis down”
followed by the event,
“APM Loop 1 Flipping…”
This indicates that although a failure was
adjacent to this chassis in the indicated
direction, this chassis did not see the problem,
but received a message from the opposite
direction of the adjacent chassis.
For APM to operate correctly, at least one FOCUS
chassis must remain in the “Down” state. Based
on the type of failure, there also could be situa-
tions where two or three adjacent FOCUS chassis
are in the “down” state.
To correctly determine the location and
probable cause of failure, we recommend that
you complete the following steps:
1. Collect the event data from each FOCUS
chassis in the loop.
Use the FCS “View All Targets” command to
display the Events List dialog box. Then
either print this data out or save it to a file for
later analysis. Make sure you collect the
following from each FOCUS chassis in the
loop:
• APM state
• APM initiator and direction of initiator,
if in the “flipped” state
•Direction and reason of failure, if in the
“down” state
The FOCUS target buffer has a limited
amount of space, so if additional events occur
after the APM event, older targets will be lost.
Therefore, it is always a good idea to save the
targets to a file at different intervals while you
are analyzing a problem. If RNC is not
working, you must do this locally.
2. Sketch a diagram, or map, of the loop on a
piece of paper so that the transceiver direc-