oracle DG 启动和关闭顺序

启动顺序：先启动备库，后启动主库

关闭顺序：先关闭主库，后关闭备库

1、正确打开备库和主库

备库:

SQL> STARTUP MOUNT;

SQL>ALTER DATABASE RECOVER MANAGED STANDBY DATABASE  DISCONNECT FROM SESSION;

主库:

SQL> STARTUP MOUNT;

SQL> ALTER DATABASE ARCHIVELOG;

SQL> ALTER DATABASE OPEN;


2、正确关闭顺序

主库

SQL>SHUTDOWN IMMEDIATE;


备库:

SQL> ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL;

SQL>SHUTDOWN IMMEDIATE;

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1.  主备切换

 1) 主库切换为备库

 alter database commit to switchover to physical standby;

主库有会话连接的时候

alter database commit to switchover to physical standby with session shutdown;

shutdown immediate

startup nomount

alter database mount standby database;

alter database recover managed standby database disconnect from session;

2) 从库切换为主库

alter database commit to switchover to primary;

shutdown immediate; 

startup

alter system switch logfile;

3) 从库打开只读实时应用模式

alter database recover managed standby databasecancel; 

alter database open;

alter database recover managed standby database using current logfile disconnect;

4) 检查切换状态

select open_mode,database_role,db_unique_name from v$database;