Trouble Notifications; Alarm Characteristics; Condition Characteristics; Severities - Cisco ONS 15600 SDH Troubleshooting Manual

Chapter 2 Alarm Troubleshooting

2.5 Trouble Notifications

The ONS 15600 SDH system reports trouble by utilizing standard alarm and condition characteristics,
standard severities following the rules in Telcordia GR-253-CORE, and graphical user interface (GUI)
state indicators. These notifications are described in the following paragraphs.
The ONS 15600 SDH uses standard Telcordia categories to characterize levels of trouble. The system
reports trouble notifications as alarms and status or descriptive notifications (if configured to do so) as
conditions in the CTC Alarms window. Alarms typically signify a problem that the user needs to remedy,
such as a loss of signal. Conditions do not necessarily require troubleshooting.

2.5.1 Alarm Characteristics

The ONS 15600 SDH uses standard alarm entities to identify what is causing trouble. All alarms stem
from hardware, software, environment, or operator-originated problems whether or not they affect
service. Current alarms for the network, CTC session, node, or card are listed in the Alarms tab. (In
addition, cleared alarms are also found in the History tab.)

2.5.2 Condition Characteristics

Conditions include any problem detected on an ONS 15600 SDH shelf. They might include standing or
transient notifications. A snapshot of all current raised, standing conditions on the network, node, or card
can be retrieved in the CTC Conditions window or using TL1's set of RTRV-COND commands. (In
addition, some but not all cleared conditions are also found in the History tab.)
For a comprehensive list of all conditions, refer to the Cisco ONS SDH TL1 Command Guide. For a
comprehensive list of all transient conditions, see

2.5.3 Severities

The ONS 15600 SDH uses Telcordia-devised standard severities for alarms and conditions:
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July 2010
A Critical (CR) alarm generally indicates severe, Service-Affecting (SA) trouble that needs
immediate correction.
A Major (MJ) alarm is a serious alarm, but the trouble has less impact on the network.
Minor (MN) alarms generally are those that do not affect service. For example, the automatic
protection switching (APS) byte failure (APSB) alarm indicates that line terminating equipment
(LTE) detects a byte failure on the signal that could prevent traffic from properly executing a traffic
switch.
Not Alarmed (NA) conditions are information indicators, such as for the free-running
synchronization (FRNGSYNC) state. They might or might not require troubleshooting, as indicated
in the entries.
Not Reported (NR) conditions occur as a secondary result of another event. For example, the alarm
indication signal (AIS), with severity NR, is inserted by a downstream node when an LOS (CR or
MJ) alarm occurs upstream. These conditions do not in themselves require troubleshooting, but are
to be expected in the presence of primary alarms.
Chapter 3, "Transient Conditions."
Cisco ONS 15600 SDH Troubleshooting Guide, R8.0
2.5 Trouble Notifications
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