[ORACLE DATAGUARD] switchover的過程

1.檢查主庫的狀態：

SQL> SELECT SWITCHOVER_STATUS FROM V$DATABASE;

SWITCHOVER_STATUS

--------------------

TO STANDBY

2.將主庫設置為standby role

 alter database commit to switchover to physical standby; 

 shutdown immediate;

 startup mount;

3.將standby轉為primary

SQL> select NAME ,DB_UNIQUE_NAME ,open_mode,DATABASE_ROLE from v$database; 

NAME  DB_UNIQUE_NAME OPEN_MODE      DATABASE_ROLE

--------- ------------------------------ -------------------- ----------------

ORCL  sty MOUNTED      PHYSICAL STANDBY

SQL> SELECT SWITCHOVER_STATUS FROM V$DATABASE; 

SWITCHOVER_STATUS

--------------------

TO PRIMARY

alter database commit to switchover to primary; 

alter database open; 

SQL> select NAME ,DB_UNIQUE_NAME ,open_mode,DATABASE_ROLE from v$database; 

NAME  DB_UNIQUE_NAME OPEN_MODE      DATABASE_ROLE

--------- ------------------------------ -------------------- ----------------

ORCL  sty READ WRITE      PRIMARY

4.原來的primary庫上執行：

alter database recover managed standby database disconnect from session; 

SQL> select NAME ,DB_UNIQUE_NAME ,open_mode,DATABASE_ROLE from v$database; 

NAME  DB_UNIQUE_NAME OPEN_MODE      DATABASE_ROLE

--------- ------------------------------ -------------------- ----------------

ORCL  pri MOUNTED      PHYSICAL STANDBY