read write方式打开PHYSICAL STANDBY,闪回和还原测试

以下大部分都在STANDBY执行,主库执行(两次)的会提示

【STANDBY read write方式打开测试】
检查standby状态
SQL> SELECT NAME,DATABASE_ROLE,OPEN_MODE,SWITCHOVER_STATUS FROM V$DATABASE;

NAME DATABASE_ROLE OPEN_MODE SWITCHOVER_STATUS
--------- ---------------- -------------------- --------------------
testdb PHYSICAL STANDBY MOUNTED NOT ALLOWED

FLASHBACK_ON要打开,以便闪回
SQL> SELECT FLASHBACK_ON FROM V$DATABASE;

FLASHBACK_ON
------------------
NO

SQL> alter database flashback on;

Database altered.

闪回恢复区设置,其中大小根据短期产生日志的大小估算
SQL> set line 200
SQL> show parameter db_recovery_file_dest

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest string /u01/app/oracle/fast_recovery_area
db_recovery_file_dest_size big integer 167280M

取消日志应用,刚提前cancel了
SQL> alter database recover managed standby database cancel;
alter database recover managed standby database cancel
*
ERROR at line 1:
ORA-16136: Managed Standby Recovery not active

创建还原点
SQL> create restore point restore_point_readonly guarantee flashback database;

Restore point created.

主库日志切换,暂时日志同步
SQL> alter system archive log current;
System altered.

SQL> alter system set log_archive_dest_state_2=defer;
System altered.

激活standby为read write并open
SQL> alter database activate standby database;

Database altered.

SQL> select name,open_mode,database_role,db_unique_name from v$database;

NAME OPEN_MODE DATABASE_ROLE DB_UNIQUE_NAME
--------- -------------------- ---------------- ------------------------------
testdb MOUNTED PRIMARY testdbdg2

SQL> alter database open;

Database altered.

SQL> set timing on;
SQL> select name,open_mode,database_role,db_unique_name from v$database;

NAME OPEN_MODE DATABASE_ROLE DB_UNIQUE_NAME
--------- -------------------- ---------------- ------------------------------
testdb READ WRITE PRIMARY testdbdg2

Elapsed: 00:00:00.00

write测试
SQL> create table scott.t as select * from dba_objects;

Table created.

Elapsed: 00:00:02.33
SQL> select count(*) from scott.t;

COUNT(*)
----------
98160

Elapsed: 00:00:00.01
SQL> truncate table scott.t;

Table truncated.

Elapsed: 00:00:09.43
SQL> select count(*) from scott.t;

COUNT(*)
----------
0

Elapsed: 00:00:00.00
SQL> drop table scott.t;

Table dropped.

Elapsed: 00:00:01.44

测试完成了之后再回到某一个时间点,这个时间点要确定好

【闪回测试】
SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.

SQL> startup mount;
ORACLE instance started.

Total System Global Area 4.2758E+10 bytes
Fixed Size 2262656 bytes
Variable Size 2.7380E+10 bytes
Database Buffers 1.5301E+10 bytes
Redo Buffers 74420224 bytes
Database mounted.

可以select sysdate- 5/1440 from dual; 确定需要闪回的时间

SQL> flashback database to timestamp sysdate- 5/1440;

Flashback complete.

Elapsed: 00:02:19.84
SQL>
SQL> alter database open resetlogs;

Database altered.

Elapsed: 00:02:02.26
SQL> select count(*) from scott.t;

COUNT(*)
----------
98160

Elapsed: 00:00:00.03


【还原测试】(到standby状态)

SQL> startup mount force
ORACLE instance started.

Total System Global Area 4.2758E+10 bytes
Fixed Size 2262656 bytes
Variable Size 2.7380E+10 bytes
Database Buffers 1.5301E+10 bytes
Redo Buffers 74420224 bytes
Database mounted.

SQL> flashback database to restore point restore_point_readonly;
Flashback complete.

再次回到PHYSICAL STANDBY
SQL> alter database convert to physical standby;
Database altered.

再次强制mount,应用日志
SQL> startup mount force
ORACLE instance started.

Total System Global Area 4.2758E+10 bytes
Fixed Size 2262656 bytes
Variable Size 2.7380E+10 bytes
Database Buffers 1.5301E+10 bytes
Redo Buffers 74420224 bytes
Database mounted.

SQL> alter database recover managed standby database disconnect from session;
Database altered.

主库(执行)启用日志
SQL> alter system set log_archive_dest_state_2=enable;
System altered.

SQL> alter system archive log current;
System altered.

主备alter日志观察是否正常

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