16 Troubleshooting Oracle Net Services

Oracle Net Services provides methods for understanding, testing and resolving network problems. Oracle Database includes utilities, and log and trace files for testing and diagnosing network connection and problems.

The TNSPING and TRCROUTE utilities test connectivity. The log and trace files keep track of the interaction between network components as errors occur. Evaluating this information helps to diagnose and troubleshoot network problems.

Understand the common testing procedures and network errors, and outline procedures for resolving problems. Also, learn methods for logging and tracing error information to diagnose and troubleshoot more complex network problems.

• Understanding Automatic Diagnostic Repository
  The Automatic Diagnostic Repository (ADR) (ADR) is a system-wide tracing and logging central repository.
• Diagnosing Oracle Net Services
  Any underlying fault, noticeable or not, is reported by Oracle Net Services with an error number or message. The error number and message provide useful information for diagnosing the problem, but may not always identify the actual problem.
• Resolving the Most Common Error Messages for Oracle Net Services
  Due to the complexity of network communications, network errors may originate from a variety of sources, for a variety of reasons. If an error occurs, then applications such as SQL*Plus, that depend on network services from Oracle Net Services, normally generate an error message.
• Troubleshooting Suggestions for Oracle Net Services
  These are the suggestions for diagnosing network problems and troubleshooting Oracle Connection Manager in Traffic Director Mode.
• Example of Troubleshooting a TNS-12154 Error
  This section offers some solutions for the TNS-12154 error. The TNS-12154 error is encountered when SQL*Net cannot find the connect identifier specified for a connection in the tnsnames.ora file or other naming adapter.
• Logging Error Information for Oracle Net Services
  All errors encountered by Oracle Net Services are appended to a log file for evaluation by a network or database administrator. The log file provides additional information for an administrator about on-screen error messages. The error stack in the log file shows the state of the software at various layers.
• Tracing Error Information for Oracle Net Services
  Tracing produces a detailed sequence of statements that describe network events as they are run. Tracing an operation enables you to obtain more information about the internal operations of the components of Oracle Net Services than is provided in a log file.
• Contacting Oracle Support Services
  Some messages recommend contacting Oracle Support Services to report a problem. When you contact Oracle Support Services, have this information available.