031_DG_1_OPENTEST

1. 啟動 flashback database功能

1.1 檢查 Cold Standby DB 是否開始 archive log mode  注意紅字

SQL>
archive log list
Database log mode Archive Mode
Automatic archival Enabled
Archive destination /u01/app/oracle/archivelog
Oldest online log sequence 45
Next log sequence to archive 47
Current log sequence 47
SQL>

1.2 設定 flashback 相關參數

注意 資料夾要存在，不然要先建立
這邊要求的空間，不一定要有，反正只是測試一下而以，不用擔心

[oracle]$ mkdir -p /data/flash_recovery_area
[oracle]$ SS

SQL>
alter system set db_recovery_file_dest_size=100g;
alter system set db_recovery_file_dest='/data/flash_recovery_area';
alter system set db_flashback_retention_target=1440;

1.3 先暫停 Cold Standby apply，並確認 Standby database in mount mode

SQL>
alter database recover managed standby database cancel;
select open_mode from v$database;

OPEN_MODE
--------------------
MOUNTED

如果出現 READ ONLY  也沒關系

1.4 開啟 flashback database 功能

SQL>
alter database flashback on;

Database altered.

1.5 重啟 Cold Standby apply

SQL>
ALTER DATABASE RECOVER MANAGED STANDBY DATABASE USING CURRENT LOGFILE DISCONNECT;


Database altered.

Prod Alter log  會產生以下的字眼
***************************************************
LGWR: Setting 'active' archival for destination LOG
***************************************************

2. Active Cold Standby 前準備 on Standby database

2.1 停止 cold standby db apply

SQL>
alter database recover managed standby database cancel;

Database altered.

2.2 建立還原點

SQL>
create restore point before_open_standby guarantee flashback database;

Restore point created.

2.3 確認所建立的還原點 有Select 到即可

SQL>
select scn, storage_size, time, name from v$restore_point;

SCN STORAGE_SIZE TIME
---------- ------------ ---------------------------------------------------------------------------
NAME
--------------------------------------------------------------------------------------------------------------------------------
1481019 52428800 08-APR-17 08.23.39.000000000 PM
BEFORE_OPEN_STANDBY


SQL>

3. Active Cold Standby 前準備 on Primary database

3.1 switch log file

SQL>
alter system switch logfile;

System altered.

3.2 暫停 archive log 歸檔至standby database

SQL>
alter system set log_archive_dest_state_2=defer ;

System altered.