一、最大性能轉換至最大可用

確認主庫模式：

[email protected] hey~2->select protection_mode,protection_level from v$database;

PROTECTION_MODE PROTECTION_LEVEL
-------------------- --------------------
MAXIMUM PERFORMANCE MAXIMUM PERFORMANCE

確認備庫模式：

[email protected] hey~1->select name,protection_mode,database_role,switchover_status from v$database;

NAME PROTECTION_MODE DATABASE_ROLE SWITCHOVER_STATUS
--------- -------------------- ---------------- --------------------
ENMO1 MAXIMUM PERFORMANCE PHYSICAL STANDBY TO PRIMARY

修改參數：alter system set LOG_ARCHIVE_DEST_2= ‘SERVICE=enmo2 ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=enmo2‘;

Database altered.

模式轉換

[email protected] hey~1->alter database set standby database to maximize availability;

Database altered.

主庫確認模式：

[email protected] hey~2->select name,protection_mode,database_role,switchover_status from v$database;

NAME PROTECTION_MODE DATABASE_ROLE SWITCHOVER_STATUS

備庫確認模式：

[email protected] hey~1->select name,protection_mode,database_role,switchover_status from v$database;

NAME PROTECTION_MODE DATABASE_ROLE SWITCHOVER_STATUS
--------- -------------------- ---------------- --------------------
ENMO1 MAXIMUM AVAILABILITY PHYSICAL STANDBY NOT ALLOWED

二、最大可用切換到最大保護

[email protected] hey~1->alter database set standby database to maximize protection;

Database altered.

[email protected] hey~1->select name,protection_mode,database_role,switchover_status from v$database;

NAME PROTECTION_MODE DATABASE_ROLE SWITCHOVER_STATUS
--------- -------------------- ---------------- --------------------
ENMO1 MAXIMUM PROTECTION PHYSICAL STANDBY TO STANDBY

『ORACLE』 DG性能轉換（11g）