SQL> select * from v$version;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
PL/SQL Release 11.2.0.1.0 - Production
CORE    11.2.0.1.0      Production
TNS for Linux: Version 11.2.0.1.0 - Production
NLSRTL Version 11.2.0.1.0 - Production

备库介绍

SQL> set lines 1000
SQL> select db_unique_name,open_mode,database_role,switchover_status from v$database;  


DB_UNIQUE_NAME                 OPEN_MODE            DATABASE_ROLE    SWITCHOVER_STATUS
------------------------------ -------------------- ---------------- --------------------
un_dg19                        READ ONLY WITH APPLY PHYSICAL STANDBY NOT ALLOWED


SQL> select * from v$version;


BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
PL/SQL Release 11.2.0.1.0 - Production
CORE    11.2.0.1.0      Production
TNS for Linux: Version 11.2.0.1.0 - Production
NLSRTL Version 11.2.0.1.0 - Production


模似主库服务器电源故障，无法启动故障

在主库上shutdown abort
SQL> select db_unique_name from v$database;


DB_UNIQUE_NAME
------------------------------
un_dg18


SQL> shutdown abort;
ORACLE instance shut down.
SQL> 



2.3 强制激活备库：

sql> alter database recover managed standby database cancel;
sql> recover standby database until cancel;   ---提示输入日志信息。如没有直接输cancel

sql>alter database activate standby database;
sql>shutdown immediate;

sql>startup