Alert Files

Onur ARDAHANLI

2 years ago

In today’s article, we will be learning about the Alert files that we will write about the errors and changes in the Database.

This file is located in the directory specified in the BACKGROUND_DUMP_DEST parameter with the name alert_<SID>.log.

	SQL> show parameter background_dump
	
	NAME                                 TYPE        VALUE
	------------------------------------ ----------- ------------------------------
	background_dump_dest                 string      /oracle/diag/rdbms/onurdb/ONURDB/trace

SQL> show parameter background_dump

NAME TYPE VALUE

------------------------------------ ----------- ------------------------------

background_dump_dest string /oracle/diag/rdbms/onurdb/ONURDB/trace

Or we can find it by querying the v$parameter view.

	SQL> SELECT NAME, VALUE FROM V$PARAMETER WHERE NAME like '%background%';
	
	NAME
	--------------------------------------------------------------------------------
	VALUE
	--------------------------------------------------------------------------------
	background_core_dump
	partial
	
	background_dump_dest
	/oracle/diag/rdbms/onurdb/ONURDB/trace

SQL> SELECT NAME, VALUE FROM V$PARAMETER WHERE NAME like '%background%';

NAME

--------------------------------------------------------------------------------

VALUE

--------------------------------------------------------------------------------

background_core_dump

partial

background_dump_dest

/oracle/diag/rdbms/onurdb/ONURDB/trace

In the Alert File:

Opening-closing the database,

Add-delete redo log group,

Adding-deleting tablespace,

parameter changes,

ORA errors are found.

Below is a short excerpt from the alert file.

	ALTER DATABASE   MOUNT
	Successful mount of redo thread 1, with mount id 469055364
	Database mounted in Exclusive Mode
	Lost write protection disabled
	Completed: ALTER DATABASE   MOUNT
	Mon Jun 29 17:40:25 2015
	ALTER DATABASE OPEN
	Thread 1 opened at log sequence 134
	  Current log# 2 seq# 134 mem# 0: /oracle/ora11g/data_ONURDB/ONURDB/redo02.log
	Successful open of redo thread 1
	
	ALTER DATABASE CLOSE NORMAL
	Mon Jun 29 17:32:49 2015
	SMON: disabling tx recovery
	SMON: disabling cache recovery
	Mon Jun 29 17:32:49 2015
	Shutting down archive processes
	Archiving is disabled
	Archive process shutdown avoided: 0 active
	Thread 1 closed at log sequence 134
	Successful close of redo thread 1
	Completed: ALTER DATABASE CLOSE NORMAL
	ALTER DATABASE DISMOUNT
	Shutting down archive processes
	Archiving is disabled
Completed: ALTER DATABASE DISMOUNT

ALTER DATABASE MOUNT

Successful mount of redo thread 1, with mount id 469055364

Database mounted in Exclusive Mode

Lost write protection disabled

Completed: ALTER DATABASE MOUNT

Mon Jun 29 17:40:25 2015

ALTER DATABASE OPEN

Thread 1 opened at log sequence 134

Current log# 2 seq# 134 mem# 0: /oracle/ora11g/data_ONURDB/ONURDB/redo02.log

Successful open of redo thread 1

ALTER DATABASE CLOSE NORMAL

Mon Jun 29 17:32:49 2015

SMON: disabling tx recovery

SMON: disabling cache recovery

Mon Jun 29 17:32:49 2015

Shutting down archive processes

Archiving is disabled

Archive process shutdown avoided: 0 active

Thread 1 closed at log sequence 134

Successful close of redo thread 1

Completed: ALTER DATABASE CLOSE NORMAL

ALTER DATABASE DISMOUNT

Shutting down archive processes

Archiving is disabled

Completed: ALTER DATABASE DISMOUNT

See Latest Logs

The last 1000 records coming to the alert file can be seen as follows.

tail -1000f /u01/app/oracle/diag/rdbms/mwdb/mwdb1/trace/alert_mwdb1.log

1	tail -1000f /u01/app/oracle/diag/rdbms/mwdb/mwdb1/trace/alert_mwdb1.log