以只读方式打开PHYSICAL STANDBY数据库，进行测试，然后还原

以只读方式打开PHYSICAL STANDBY数据库，进行测试，然后还原

a. 检查standby的状态
sql> select name,database_role,open_mode,switchover_status from v$database;
name      database_role    open_mode  switchover_status
--------- ---------------- ---------- --------------------
orcldb    physical standby mounted    not allowed

b.判断flashback_on是否开启
SQL> select flashback_on from v$database;
FLASHBACK_ON
------------------
YES

c.闪回恢复区设置检测
SQL> show parameter db_recovery_file_dest
NAME                                TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest                string      /u01/Oracle/flash_recovery_are
a
db_recovery_file_dest_size          big integer 2G

d.取消日志应用
SQL> alter database recover managed standby database cancel;
Database altered.

e.创建还原点
SQL> create restore point restore_point_readonly guarantee flashback database;
Restore point created.

f.在主库上进行日志切换,日志发送设置为延迟
SQL> alter system archive log current;
System altered.
SQL> alter system set log_archive_dest_state_2=defer;
System altered.

 
h.激活备库到read write状态，并打开
SQL> alter database activate standby database;
Database altered.
SQL> alter database open;
Database altered.
SQL> select name,open_mode,database_role,db_unique_name from v$database;
NAME      OPEN_MODE  DATABASE_ROLE    DB_UNIQUE_NAME
--------- ---------- ---------------- ------------------------------
ORCLDB    READ WRITE PRIMARY          PHYSTDBY

i.进行read write测试
SQL> create table scott.t as select * from dba_objects;
Table created.
SQL> select count(*) from scott.t;
COUNT(*)
----------
49745
SQL> truncate table scott.t;
Table truncated.
SQL> select count(*) from scott.t;
COUNT(*)
----------
0

j.测试结束，准备还原备库。  先强制启动到mount状态，然后进行数据库闪回
 
SQL> startup mount force
ORACLE instance started.
Total System Global Area  390070272 bytes
Fixed Size                  2021024 bytes
Variable Size            142608736 bytes
Database Buffers          243269632 bytes
Redo Buffers                2170880 bytes
Database mounted.
SQL> flashback database to restore point restore_point_readonly;
Flashback complete.

k.将数据库转换为physical standby
SQL> alter database convert to physical standby;
Database altered.

 
l.再次强制启动到mout状态，，然后应用日志
 
SQL> startup mount force
ORACLE instance started.
Total System Global Area  390070272 bytes
Fixed Size                  2021024 bytes
Variable Size            142608736 bytes
Database Buffers          243269632 bytes
Redo Buffers                2170880 bytes
Database mounted.
SQL> alter database recover managed standby database disconnect from session;
Database altered.

m.在主库把日志传送启用，切换日志
SQL> alter system set log_archive_dest_state_2=enable;
System altered.
SQL> alter system archive log current;
System altered.

n.观察备库日志，即可发现已经正常切换至physical standby，应用日志正常。
 
alter database recover managed standby database disconnect from session
Sun Jan  5 07:43:47 2014
Attempt to start background Managed Standby Recovery process (PHYSTDBY)
MRP0 started with pid=22, OS id=13951
Sun Jan  5 07:43:47 2014
MRP0: Background Managed Standby Recovery process started (PHYSTDBY)
Managed Standby Recovery not using Real Time Apply
Clearing online redo logfile 1 /u01/oracle/oradata/ORCLDB/redo01.log
Clearing online log 1 of thread 1 sequence number 1
Sun Jan  5 07:43:53 2014
Completed: alter database recover managed standby database disconnect from session
Sun Jan  5 07:43:55 2014
Clearing online redo logfile 1 complete
Media Recovery Log /u01/oracle/arch1/PHYSTDBY/1_39_795970778.dbf
Media Recovery Log /u01/oracle/arch1/PHYSTDBY/1_40_795970778.dbf
Media Recovery Waiting for thread 1 sequence 41
Sun Jan  5 07:44:56 2014
Redo Shipping Client Connected as PUBLIC
-- Connected User is Valid
RFS[1]: Assigned to RFS process 13953
RFS[1]: Identified database type as 'physical standby'
Primary database is in MAXIMUM AVAILABILITY mode
Changing standby controlfile to RESYNCHRONIZATION level
Sun Jan  5 07:44:56 2014
RFS LogMiner: Client disabled from further notification
Primary database is in MAXIMUM AVAILABILITY mode
Changing standby controlfile to MAXIMUM AVAILABILITY level
RFS[1]: Successfully opened standby log 4: '/u01/oracle/oradata/ORCLDB/stdby_redo04.log'
Sun Jan  5 07:44:56 2014
Redo Shipping Client Connected as PUBLIC
-- Connected User is Valid
RFS[2]: Assigned to RFS process 13955
RFS[2]: Identified database type as 'physical standby'
RFS[2]: Successfully opened standby log 5: '/u01/oracle/oradata/ORCLDB/stdby_redo05.log'
Sun Jan  5 07:45:01 2014
Media Recovery Log /u01/oracle/arch1/PHYSTDBY/1_41_795970778.dbf
Media Recovery Waiting for thread 1 sequence 42 (in transit)
Sun Jan  5 07:45:16 2014
Redo Shipping Client Connected as PUBLIC
-- Connected User is Valid
RFS[3]: Assigned to RFS process 13959
RFS[3]: Identified database type as 'physical standby'

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