Collecting diagnostic data

The primary resource for diagnostic data is logs. Logs are records of text messages and trace data that is generated by the software and written to an output destination, such as a console screen or a file.

Typically, an OMEGAMON® monitoring agent on z/OS® does not display messages at the Tivoli® Enterprise Portal. Instead, messages are sent to more typical z/OS output locations, such as SYSOUT data sets or spool files or, more rarely, to the z/OS system console. Logging is enabled on all monitoring agents by default.

Tracing is the recording of the processing of a computer program or transaction. Trace logs capture information about the operating environment to help you diagnose problems when component software fails to operate as intended. The principal log type for Tivoli Management Services and monitoring agents that share those services is the reliability, availability, and serviceability (RAS1) trace log.

When the Tivoli Management Services z/OS components are initialized, RAS1 service initialization is one of the first processes started. The RAS1 trace log mechanism is available on the Tivoli Enterprise Monitoring Server, the Tivoli Enterprise Portal Server, and the monitoring agents. Most logs are located in a logs subdirectory on the host computer. RAS logs are in the English language only.

By default, an OMEGAMON monitoring agent on z/OS has minimal tracing enabled. The RAS1=ERROR setting means that only error messages are captured. When you report a problem, IBM® Software Support might ask you to enable a more in-depth and detailed form of tracing, such as one of those discussed under Syntax for RAS1 traces. IBM Software Support uses the information captured by trace logging to trace a problem to its source or to determine why an error occurred. The default configuration for trace logging, such as the level of trace logging, depends on the source of the trace logging. Trace logging is always enabled.

Note: There is CPU and I/O overhead that is associated with detailed RAS1 tracing that might degrade performance of the monitoring agent. Restore RAS1 tracing to the minimal KBB_RAS1=ERROR after problem diagnosis is completed.

Log files and trace information are provided in a common fashion across all monitoring agents on z/OS and the z/OS components of the Tivoli Management Services. See RAS1 tracing to understand the locations of log and trace files for the monitoring agent and the Tivoli Management Services components on z/OS.

For the locations for log files for distributed components, see the IBM Tivoli Monitoring: Troubleshooting Guide.