Each database has an alert log file, which contains a chronological(sequential order in which they occurred) log of database messages and errors. Oracle will automatically create a new alert log file whenever the old one is deleted.
The alert log includes the following errors and log messages:
- All internal errors (ORA-600), block corruption errors (ORA-1578), and deadlock errors (ORA-60)
- Administrative operations such as DDL statements and the SQL*Plus commands STARTUP, SHUTDOWN, ARCHIVE LOG, and RECOVER
- Several messages and errors relating to the functions of shared server and dispatcher processes
- Errors during the automatic refresh of a materialized view
How to Find the Location of alert log file in Oracle 11g
SQL> select name from v$database;
NAME
---------
TEST11
alert.log file is written to the directory specified by the background_dump_dest parameter. To view alert log, first you need to find it’s location using show parameter command.
SQL> show parameter background_dump_dest
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
background_dump_dest string /u01/orahow/diag/rdbms/test11/TEST11/trace
You can also get the same result using this sql:
SQL> show parameter background
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
background_core_dump string partial
background_dump_dest string /u01/orahow/diag/rdbms/test11/TEST11/trace
Copy the above value to find the exact name and location of alert log using ls command:
[oracle@orahow ~]$ ls -ltr /u01/orahow/diag/rdbms/test11/TEST11/trace/al*
-rw-r----- 1 oracle dba 1901154 Nov 24 04:00 //u01/orahow/diag/rdbms/test11/TEST11/trace/alert_TEST11.log
To view alert log you can use tail command with options and filename.
[oracle@orahow ~]$ tail -20f /u01/orahow/diag/rdbms/test11/TEST11/trace/ alert_TEST11.log
In the following output you will see the last 20 lines of the alert log, but if you want to see more number of lines (ex: 100 line) you can use 100f like that.
Its nice– I learnt something today
thanks..its really help me..
how to read last 20 lines from alert log on windows
Hello Raaz, you can try adrci feature to see the alert log. Try once: adrci> show alert -tail 20