Knowledge Base

Location of alert.log file

The alert.log file contain messages related to the startup and running of a specific database.



The name of the alert.log file is:

alert<ORACLE_SID>.log

on Windows, or

alert_<ORACLE_SID>.log

On Unix/Linux


The alert.log file normally is in the $ORACLE_BASE/<ORACLE_SID>/bdump location, or since Oracle 11g in the database specific location in the diagnostic_dest.



If the database is running, you can issue following select to be able to identify the location of the background_dump_dest:

SQL> select value from v$parameter where name='background_dump_dest';

VALUE
--------------------------------------------------------------------------------
/oracle/diag/diag/rdbms/ora11g/ORA11G/trace

To find the location of the diagnostic_dest, one can use the following select:

SQL> select value from v$parameter where name='diagnostic_dest';

VALUE
--------------------------------------------------------------------------------
/oracle/diag/

In order to know the current ORACLE_SID, you can use following select:

SQL> select name from v$database;

NAME
---------------------------
ORA11G

In our example, because we are on Linux, the name of the alert.log file will be:

/oracle/diag/diag/rdbms/ora11g/ORA11G/trace/alert_ORA11G.log
If the alert.log file is not in any of these locations, or the parameters are not set, the alert.log file will be in your %ORACLE_HOME/rdbms/trace directory.
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