User guide

C-44
Cisco Media Gateway Manager 5.0 User Guide
OL-5461-02
Appendix C Troubleshooting
Configuration Center, Chassis View, Diagnostic Center and Statistics Report Problems
6. Alarm List displays mostly active alarms, however some 'Events' are also displayed. For details on
'Events vs. Alarms' see Figure 7.5.2, "INF: XML Schema for alarm rules," on page 153.
7. Some alarms result in the network element having a different alarm severity then the actual alarm.
For details on 'Object Severity vs. Alarm Severity' see Figure 7.5.3, "INF: Alarm Severity vs. Object
Severity," on page 156.
Alarms for various network elements are stored in memory cache in the NMServer Object Tree. GUI
clients register for alarms from NMServer by providing the FDN of the network element for which they
would like alarms for. All alarms for network elements under the FDN registered will be send if the
parent FDN is registered. GUI clients may also update alarms, such as flag an alarm as acknowledged,
or manually clear an alarm. These updates are done via the 'Alarm Repository' component of NMServer.
Figure C-2 illustrates the client/server architecture for alarm components in NMServer.
Figure C-2 Client/Server Architecture for Alarm Components
C.6.5.2 XML Schema for Alarm Rules
Alarm rules are defined in XML, specifically a file named $HOME/xml/ruledata.xml. These alarm rules
are read once when NMServer starts. When events are processed, the rules are queried from memory to
determine what action with regard to alarms, should be taken on the event. There are 3 types of alarm
rules defined in the XML schema: Correlated, Correlated Bitmap, and Transient. Specifics on each of
these three types follows.
1. Correlated Alarm Rule Type
The correlated alarm rule type is the most common in ruledata.xml. This rule is used when a network
element can only be in one of many states at any one time. If the entity were to change states, then the
previous alarm state would be cleared. Most network elements managed by Cisco MGM fall into this
category. A simple example is DB SyncUp status of a node. The syncup status can be one of 'Partial
Syncup', 'Syncup Failed', or 'In Sync'. Any one of these states correlates out any other. See Figure C-3.
Alarm Client
Network Monitor Server
(Alarm Components)
Alarm Service
Client
Alarm Repository
Alarm Observer
Client Handler
Object Tree
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Alarm Service