listener.ora Configuration Guide

The listener.ora file is an essential configuration file for Oracle databases. It specifies the settings for the database listener, enabling communication between the database and client applications. Below is an overview of its structure and common configuration parameters.

Key Sections of listener.ora

  1. Listener Settings

  2. Defines listener names and network protocol addresses.

  3. Global Database Service Configuration

  4. Specifies global database names and associated service identifiers.

  5. Logging and Tracing Parameters

  6. Configures log files and trace levels for better debugging and tracking.

Example Configuration of listener.ora

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(HOST = myhost)(PORT = 1521))
    )
  )

SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (GLOBAL_DBNAME = mydb.example.com)
      (ORACLE_HOME = /oracle/product/12.1.0)
      (SID_NAME = mydb)
    )
  )

Important Tips

  • Always back up listener.ora before making changes.
  • Verify settings by using lsnrctl commands to start, stop, or check listener status.

Use this guide as a reference to ensure your Oracle database connections remain stable and secure.