Commands and parameters for Oracle archive Mode

Oracle databases can run in two modes: archivelog and noarchivelog ). Archiving can improve the recoverability of Oracle databases,

Oracle databases can run in two modes: archivelog and noarchivelog ). Archiving can improve the recoverability of Oracle databases,

Commands and parameters for Oracle archive 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.

Command for checking archive mode:
SQL> archive log list
Database log mode No Archive Mode
Automatic archival Disabled
Archive destination USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence 15
Current log sequence 17

Set the archive mode:
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup mount
ORACLE instance started.

Total System Global Area 1258291200 bytes
Fixed Size 1219160 bytes
Variable Size 318768552 bytes
Database Buffers 922746880 bytes
Redo Buffers 15556608 bytes
Database mounted.

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 USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence 15
Next log sequence to archive 17
Current log sequence 17

To stop the archive mode, run the alter database noarchivelog command. Before Oracle10g, you also need to modify the initialization parameters so that the database is in the automatic archiving mode. Set the following parameter 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 archive log start during database startup.

Enable automatic archiving for the database, but the database is still in manual archiving mode after restart. 10 Gb uses db_recovery_file_dest as the storage location for archiving logs. SQL> show parameter db_recovery

NAME TYPE VALUE
Db_recovery_file_dest string/home/oracle/ora10g/flash_reco
Very_area/
Db_recovery_file_dest_size big integer 20G

You can modify the size of the parameter 'alter system set db_recovery_file_dest_size = 21474836480 '.