How to enable archive log

SQL*Plus: Release 9.2.0.1.0 - Production on Fri Jan 16 06:56:21 2004

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SQL> conn /as sysdba;
Connected.

SQL> shutdown;
Database closed.
Database dismounted.
ORACLE instance shut down.


SQL> startup mount;
ORACLE instance started.

Total System Global Area  135338868 bytes
Fixed Size                   453492 bytes
Variable Size             109051904 bytes
Database Buffers           25165824 bytes
Redo Buffers                 667648 bytes
Database mounted.


SQL> alter database archivelog;


Database altered.

SQL> alter database open;

Database altered.


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automatic enable archiving at instance startup

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SQL> alter system set log_archive_start=true scope=spfile;

System altered.

SQL> alter system set log_archive_max_processes=1;

System altered.


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manual enable archiving

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SQL> alter system set log_archive_start=false scope=spfile;

System altered.

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manual archiving online redo log file.

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SQL>
SQL> alter system archive log current;

System altered.

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automatic enable archiving after instance startup

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SQL> alter system archive log start;

System altered.


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automatic desable archiving

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SQL> alter system archive log stop;

System altered.

SQL>