oracle 单实例DG(切换篇三)

一,开篇

　　　此篇操作承接上文,必须完成DG实例搭建完成方可有执行以下内容的实例

二,切换物理备库

　　one. oracle01库命令

select switchover_status from v$database;

alter database commit to switchover to physical standby;

注意:　　上面 switchover_status 的值如果是 TO STANDBY，可以直接 switchover，如果是 sessions active，则需要在 switchover 的命 令后面加上 with session shutdown，比如 alter database commit to switchover to physical standby with session shutdown;

select status from v$instance;--检查状态

shutdown immediate

startup nomount

切换主库为备库

　　　two.standy端　

select sequence#, applied from v$archived_log where applied='YES' order by sequence#;

SQL> select sequence#, applied from v$archived_log where applied='YES' order by sequence#;

 SEQUENCE# APPLIED
---------- ---------
	 6 YES
	 7 YES
	 8 YES
	 9 YES
	10 YES
	11 YES
	12 YES
	13 YES
	14 YES
	15 YES
	16 YES

 SEQUENCE# APPLIED
---------- ---------
	17 YES
	18 YES
	19 YES

14 rows selected.
日志同步
SQL> select switchover_status from v$database;

SWITCHOVER_STATUS
--------------------
TO PRIMARY

SQL> alter database commit to switchover to primary;

Database altered.
备库切成主库

SQL> select status from v$instance;

STATUS
------------
MOUNTED

SQL> shutdown immediate
ORA-01109: database not open

Database dismounted.
ORACLE instance shut down.
SQL> startup
ORACLE instance started.

Total System Global Area 2505338880 bytes
Fixed Size		    2255832 bytes
Variable Size		  603980840 bytes
Database Buffers	 1879048192 bytes
Redo Buffers		   20054016 bytes
Database mounted.
Database opened.
SQL>

　　three.oracle01端

　　　　　　创建备日志

alter database add standby logfile ('/u01/app/oracle/oradata/oracle01/standby01.log') size 50m;
alter database add standby logfile('/u01/app/oracle/oradata/oracle01/standby02.log') size 50m;
alter database add standby logfile('/u01/app/oracle/oradata/oracle01/standby03.log') size 50m;
alter database add standby logfile('/u01/app/oracle/oradata/oracle01/standby04.log') size 50m;

　　　　　　

　　　　执行同步语句:

alter database recover managed standby database using current logfile disconnect from session;

select sequence#, applied from v$archived_log where applied='YES'order by sequence#;
 

 SQL> select sequence#, applied from v$archived_log where applied='YES'order by sequence#;

  SEQUENCE# APPLIED
 ---------- ---------
      6 YES
      6 YES
      7 YES
      7 YES
      8 YES
      8 YES
      9 YES
      9 YES
     10 YES
     10 YES
     11 YES

  SEQUENCE# APPLIED
 ---------- ---------
     11 YES
     12 YES
     12 YES
     13 YES
     13 YES
     14 YES
     14 YES
     15 YES
     15 YES
     16 YES
     16 YES

  SEQUENCE# APPLIED
 ---------- ---------
     17 YES
     17 YES
     18 YES
     19 YES
     20 YES
     21 YES

 28 rows selected.

　　four.standby执行创建数据库字段　　　

SQL> insert into dg values(2);

1 row created.

SQL> commit ;
　　
Commit complete.

　　five.oracle01执行　　　

SQL> alter database recover managed standby database cancel;

Database altered.

SQL> alter database open;

Database altered.

SQL> select * from dg;

	ID
----------
	 1
	 2

SQL>

　　　　　　切换成功

　　状态查看:

　　　　

　　　　

三,再次切oracle01为主库,standby为备库

　　　one.oracle01端执行　　　

SQL> select open_mode from v$database;

OPEN_MODE
--------------------
READ ONLY

SQL> alter database recover managed standby database using current logfile disconnect from session;

Database altered.

SQL> select open_mode from v$database;

OPEN_MODE
--------------------
READ ONLY WITH APPLY

　　　two.standby端执行　　　

SQL> select switchover_status from v$database;

SWITCHOVER_STATUS
--------------------
TO STANDBY

SQL> alter database commit to switchover to physical standby;

Database altered.

SQL> shutdown immediate
ORA-01012: not logged on
SQL> startup nomount
ORACLE instance started.

Total System Global Area 2505338880 bytes
Fixed Size		    2255832 bytes
Variable Size		  603980840 bytes
Database Buffers	 1879048192 bytes
Redo Buffers		   20054016 bytes
SQL> alter database mount standby database;

Database altered.

SQL>

　　　three.oracle01端执行

select sequence#, applied from v$archived_log where applied='YES' order by sequence#;

 SQL> select sequence#, applied from v$archived_log where applied='YES' order by sequence#;

  SEQUENCE# APPLIED
 ---------- ---------
      6 YES
      6 YES
      7 YES
      7 YES
      8 YES
      8 YES
      9 YES
      9 YES
     10 YES
     10 YES
     11 YES

  SEQUENCE# APPLIED
 ---------- ---------
     11 YES
     12 YES
     12 YES
     13 YES
     13 YES
     14 YES
     14 YES
     15 YES
     15 YES
     16 YES
     16 YES

  SEQUENCE# APPLIED
 ---------- ---------
     17 YES
     17 YES
     18 YES
     19 YES
     20 YES
     21 YES
     22 YES

 29 rows selected.

 SQL>

select switchover_status from v$database;

alter database commit to switchover to primary;

select status from v$instance;

shutdown immediate
startup

　　　four.standy端执行　　　

alter database recover managed standby database using current logfile disconnect from session;

　　　 five.oracle01端.添加数据测试　

SQL> insert into dg values(3);

1 row created.

SQL> commit;

Commit complete.

SQL> alter system switch logfile;

System altered.

　　　six.standby 数据查看

SQL>
alter database recover managed standby database using current logfile disconnect from session;SQL>

Database altered.

SQL> alter database recover managed standby database cancel;

Database altered.

SQL> alter database open;

Database altered.

SQL> select * from dg;

	ID
----------
	 1
	 2
	 3

SQL>