Maintenance
4-93160-A2-GB21-50 January 1997
Alarms
The DSU/CSU can be attached, either locally or
remotely, to an ASCII terminal or printer to display or
print alarm messages. Alarms can also be displayed on a
PC that is using a terminal emulation package.
For standalone DSU/CSUs, you can route these alarms
to the MODEM port, the COM port, or both. For
carrier-mounted DSU/CSUs, you can route them to the
COM port or dial them out using an external device.
Each alarm message contains a customer identification
to indicate which remote DSU/CSU is reporting an alarm.
For information about customer identification, refer to the
Displaying Unit Identity section in Chapter 3, Operation.
Possible alarm messages are as follows:
•Continuous Loss Of Signal detected at the x
Interface (where x is either Network or DTE).
•Alarm Cleared. Loss Of Signal condition at the x
Interface (where x is either Network or DTE).
•Continuous Out Of Frame condition detected at
the x Interface (where x is either Network or
DTE).
•Alarm Cleared. Out Of Frame condition at the x
Interface (where x is either Network or DTE).
•Alarm Indication Signal received at the x
Interface (where x is either Network or DTE).
•Alarm Cleared. Alarm Indication Signal at the x
Interface (where x is either Network or DTE).
•An Excessive Error Rate has been detected at
the Network Interface.
•Alarm Cleared. An Excessive Error Rate at the
Network Interface.
•Yellow Alarm signal received at the x Interface
(where x is either Network or DTE).
•Alarm Cleared. Yellow Alarm signal at the x
Interface (where x is either Network or DTE).
•Continuous Out Of Frame condition detected at
synchronous data port n (where n is the port
number).
•Alarm Cleared. Out Of Frame condition at
synchronous data port n (where n is the port
number).
•An Excessive Error Rate has been detected at
synchronous data port n (where n is the port
number).
•Alarm Cleared. An Excessive Error Rate at
synchronous data port n (where n is the port
number).
If two alarm conditions are detected at once, the higher
priority alarm is reported. However, if an even higher
priority alarm is detected before the first alarm is cleared,
the later alarm is not reported. (The alarms listed above
are in priority order with the highest priority listed first.)
Alarms remain active until the alarm condition is
cleared. Also, an alarm clear message is only sent when
there are no other alarms active.
For information about alarm configuration options,
refer to the Alarm Configuration Options section in
Appendix C, Configuration Options.
For troubleshooting information, refer to the
Troubleshooting section on page 4-11.