Archive Log Mode

檢查 Archive Log Mode 狀態

關閉時：

SQL> archive log list
Database log mode              No Archive Mode
Automatic archival             Disabled
Archive destination            USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence     2178
Current log sequence           2180

SQL> select log_mode, open_mode, name from v$database;

LOG_MODE     OPEN_MODE  NAME
------------ ---------- ---------
NOARCHIVELOG READ WRITE WIN 

開啟時：

SQL> archive log list
Database log mode              Archive Mode
Automatic archival             Enabled
Archive destination            /opt/oracle/arclog
Oldest online log sequence     2178
Next log sequence to archive   2180
Current log sequence           2180

第一次啟用 Archive Log

NOTE: 要啟用 Archive Log 時，必須重啟一次 DB，為了縮短 downtime，可以在停機前先設定參數 log_archive_dest_1。

設定 Archive Log 的儲存路徑

sqlplus / as sysdba

SQL> show parameters recovery_file_dest

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest                string      /opt/oracle/flash_recovery_area
db_recovery_file_dest_size           big integer 2G 

SQL> alter system set log_archive_dest_1='LOCATION=/opt/oracle/arclog' scope=spfile;
SQL> alter system set log_archive_format='mydb_%s_%t_%r.arc' scope=spfile;
SQL> show parameters log_archive; 
SQL> shutdown immediate

SQL> startup mount
SQL> show parameters log_archive
SQL> alter database archivelog;
SQL> alter databse open;
SQL> archive log list 

SQL> shutdown immediate
SQL> startup 

驗證

SQL> alter system switch logfile;

或

SQL> alter system archive log current; 

關閉 Archive Log

關閉

SQL> shutdown immediate
SQL> startup mount
SQL> alter database noarchivelog;
SQL> alter database open; 

開啟

SQL> shutdown immediate
SQL> startup mount
SQL> alter database archivelog;
SQL> alter database open;