Locations Posted by MOHAMMED ABDUL HAMEED on 12:54 PM

Alert log :

This file is where database-level errors are written and operations such as startup, shutdown, and other events are logged. 

Oracle writes to this text-based file in a chronological order when the database is running.

Oracle will automatically create a new alert log file whenever the old one is deleted.

Usage :

Whenever a problem occurs, review the alert log file.

Review the alert log file daily (if you’re the Database Administrator – DBA) to ensure errors are not occurring undetected.

Location :

Oracle will write the alert.log file to the directory as specified by the BACKGROUND_DUMP_DEST parameter. 

If this parameter is not set, the alert.log will be created in a directory below the value of the DIAGNOSTIC_DEST parameter: 

DIAGNOSTIC_DEST/diag/rdbms/DB_NAME/ORACLE_SID/trace. 

If this later parameter is not set, the alert.log file is created in the ORACLE_HOME/rdbms/trace directory.

SQL> show parameter BACKGROUND_DUMP_DEST

NAME                                    TYPE        VALUE
----------------------------- -----------    ------------------------------
background_dump_dest  string      /u01/app/oracle/diag/rdbms/oracl/trace