Enable/disable ARCHIVELOG Mode

 

　　Oracle databases can run in two modes: archivelog and noarchivelog)
　　
The archive mode can improve the recoverability of Oracle databases. Production Databases should all run in this mode. The Archive mode should be combined with the corresponding backup policies, only when the archive mode does not have a corresponding backup policy will it be troublesome.
　　
This document describes how to enable and disable the archive mode of a database.
　　
1. shutdown normal or shutdown immediate
　　
[Oracle @ jumper oracle] $ sqlplus "/as sysdba"
　　
SQL * Plus: Release 9.2.0.4.0-Production on Sat Oct 15 15:48:36 2005
　　
Copyright (c) 1982,200 2, Oracle Corporation. All rights reserved.
　　
Connected:
Oracle9i Enterprise Edition Release 9.2.0.4.0-Production
With the Partitioning option
JServer Release 9.2.0.4.0-Production
　　
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
　　
2. Start the database to the mount status.
　　
SQL> startup mount;
ORACLE instance started.
　　
Total System Global Area 101782828 bytes
Fixed Size 451884 bytes
Variable Size 37748736 bytes
Database Buffers 62914560 bytes
Redo Buffers 667648 bytes
Database mounted.
　　
3. Enable or stop archive Mode
　　
To enable the archive mode, use
　　
Alter database archivelog command.
SQL> alter database archivelog;
Database altered.
　　
SQL> alter database open;
　　
Database altered.
　　
SQL> archive log list;
Database log mode Archive Mode
Automatic archival Enabled
Archive destination/opt/oracle/oradata/conner/archive
Oldest online log sequence 148
Next log sequence to archive 151
Current log sequence 151
　　
If you need to stop the archive mode, use:
　　
Alter database noarchivelog command.
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup mount;
ORACLE instance started.
　　
Total System Global Area 101782828 bytes
Fixed Size 451884 bytes
Variable Size 37748736 bytes
Database Buffers 62914560 bytes
Redo Buffers 667648 bytes
Database mounted.
SQL> alter database noarchivelog;
　　
Database altered.
　　
SQL> alter database open;
　　
Database altered.
　　
SQL> archive log list;
Database log mode No Archive Mode
Automatic archival Enabled
Archive destination/opt/oracle/oradata/conner/archive
Oldest online log sequence 149
Current log sequence 152
　　
4. Modify the initialization parameters.
　　
Before Oracle10g, you also need to modify the initialization parameters so that the database is in the automatic archiving mode.
　　
Set the following parameters in pfile/spfile:
　　
Log_archive_start = true
　　
Restart the database. This parameter takes effect when the database is in automatic archiving mode.
　　
You can also manually execute the following commands during database startup:
　　
Archive log start
　　
Enable automatic archiving for the database, but the database is still in manual archiving mode after restart.
　　
The log_archive_start parameter has been abolished since Oracle10g.