Oracle单实例数据库迁移到Oracle RAC 环境之(3)--主备库Switchover

Oracle单实例数据库迁移到Oracle RAC 环境之(3)--主备库Switchover

系统环境：

操作系统：RedHat EL55

Oracle ： Oracle 11.2.0.1.0

集群软件：Oracle GI 11.2.0.1.0

本案例采用的是基于DataGuard的迁移方式

主备库实施切换，将RAC database切换成主库，既可以完成数据的迁移。

主库：

8:18:00 SYS@ cuug>select name,dbid,database_role,protection_mode,switchover_status from v$database;

NAME            DBID DATABASE_ROLE    PROTECTION_MODE      SWITCHOVER_STATUS

--------- ---------- ---------------- -------------------- --------------------

CUUG      1329392875 PRIMARY          MAXIMUM PERFORMANCE  TO STANDBY

备库：

SQL> select name,dbid,database_role,protection_mode,switchover_status from v$database;

NAME            DBID DATABASE_ROLE    PROTECTION_MODE      SWITCHOVER_STATUS

--------- ---------- ---------------- -------------------- --------------------

CUUG      1329392875 PHYSICAL STANDBY MAXIMUM PERFORMANCE  NOT ALLOWED

1、首先将主库（单实例）切换成备库

18:20:51 SYS@ cuug>alter database commit to switchover to standby with session shutdown ;

Database altered.

Elapsed: 00:00:25.41

18:21:25 SYS@ cuug>shutdown

ORA-01507: database not mounted

ORACLE instance shut down.

18:21:55 SYS@ cuug>startup mount;

ORACLE instance started.

Total System Global Area  418484224 bytes

Fixed Size                  1336932 bytes

Variable Size             264243612 bytes

Database Buffers          146800640 bytes

Redo Buffers                6103040 bytes

Database mounted.

18:22:03 SYS@ cuug>select name,dbid,database_role,protection_mode,switchover_status from v$database;

NAME            DBID DATABASE_ROLE    PROTECTION_MODE      SWITCHOVER_STATUS

--------- ---------- ---------------- -------------------- --------------------

CUUG      1329392875 PHYSICAL STANDBY MAXIMUM PERFORMANCE  TO PRIMARY

Elapsed: 00:00:00.01

18:22:08 SYS@ cuug>recover managed standby database disconnect from session;

Media recovery complete.

2、将备库（RAC)切换成主库

SQL> alter database commit to switchover to primary;

Database altered.

SQL> alter database open;

Database altered.

SQL> select name,dbid,database_role,protection_mode,switchover_status from v$database;

NAME            DBID DATABASE_ROLE    PROTECTION_MODE      SWITCHOVER_STATUS

--------- ---------- ---------------- -------------------- --------------------

CUUG      1329392875 PRIMARY          MAXIMUM PERFORMANCE  RESOLVABLE GAP

SQL> alter system switch logfile;

System altered.

SQL> select name,dbid,database_role,protection_mode,switchover_status from v$database;

NAME            DBID DATABASE_ROLE    PROTECTION_MODE      SWITCHOVER_STATUS

--------- ---------- ---------------- -------------------- --------------------

CUUG      1329392875 PRIMARY          MAXIMUM PERFORMANCE  TO STANDBY

@至此，DG切换成功

3、启动node2上的Instnace（stddb2）

SQL> startup

ORACLE instance started.

Total System Global Area  418484224 bytes

Fixed Size                  1336932 bytes

Variable Size             318769564 bytes

Database Buffers           92274688 bytes

Redo Buffers                6103040 bytes

ORA-01618: redo thread 2 is not enabled - cannot mount

启动失败，解决方法：

1）查看实例1的redo日志

SQL> select group#,thread#,sequence#,status,bytes from v$log;

    GROUP#    THREAD#  SEQUENCE# STATUS                BYTES

---------- ---------- ---------- ---------------- ----------

         1          1         31 CURRENT            52428800

         2          1         29 INACTIVE           52428800

         3          1         30 ACTIVE             52428800

缺少thread 2的日志，对于RAC应该有两个thread ！

2）添加thread 2日志组

SQL> alter database add logfile thread 2 ('+dg1','+rcy1') size 50m;

Database altered.

SQL> alter database add logfile thread 2 ('+dg1','+rcy1') size 50m;

Database altered.

SQL> alter database add logfile thread 2 ('+dg1','+rcy1') size 50m;

Database altered.

SQL> select group#,member from v$logfile order by 1;

    GROUP# MEMBER

---------- --------------------------------------------------

         1 +DG1/stddb/onlinelog/redo01a.log

         1 +RCY1/stddb/onlinelog/redo01b.log

         2 +RCY1/stddb/onlinelog/redo02b.log

         2 +DG1/stddb/onlinelog/redo02a.log

         3 +DG1/stddb/onlinelog/redo03a.log

         3 +RCY1/stddb/onlinelog/redo03b.log

         4 +DG1/stddb/onlinelog/group_4.280.848169735

         4 +RCY1/stddb/onlinelog/group_4.287.848169817

         5 +DG1/stddb/onlinelog/group_5.281.848169749

         5 +RCY1/stddb/onlinelog/group_5.288.848169827

         6 +DG1/stddb/onlinelog/group_6.282.848169759

    GROUP# MEMBER

---------- --------------------------------------------------

         6 +RCY1/stddb/onlinelog/group_6.289.848169831

12 rows selected.

3）激活thread 2

SQL> alter database enable thread 2;

Database altered.

4）再从node 2 open database

SQL> alter database open;

alter database open

*

ERROR at line 1:

ORA-01092: ORACLE instance terminated. Disconnection forced

ORA-30012: undo tablespace 'UNDOTBS2' does not exist or of wrong type

Process ID: 10707

Session ID: 1 Serial number: 3

看来是缺少undo tablespace；

回到node 1添加表空间：

SQL> alter system set db_create_file_dest='+dg1';

System altered.

SQL> create undo tablespace undotbs2;

Tablespace created.

重新在node2上启动Instance：

SQL> startup 

ORACLE instance started.

Total System Global Area  418484224 bytes

Fixed Size                  1336932 bytes

Variable Size             318769564 bytes

Database Buffers           92274688 bytes

Redo Buffers                6103040 bytes

Database mounted.

Database opened.

SQL> show parameter undo

NAME                                 TYPE        VALUE

------------------------------------ ----------- ------------------------------

undo_management                      string      AUTO

undo_retention                       integer     900

undo_tablespace                      string      UNDOTBS2

SQL> 

@至此，node2上的Instance 启动完毕，数据迁移完成。

4、将RAC上的database和Instance注册到CRS

由于RAC是基于CRS管理的，需要把database和instance注册到CRS里进行管理

1)注册数据库

[oracle@node1 ~]$ srvctl add database -d stddb -o $ORACLE_HOME -n cuug

2）注册实例

[oracle@node1 ~]$ srvctl add instance -d stddb -i stddb1 -n node1

[oracle@node1 ~]$ srvctl add instance -d stddb -i stddb2 -n node2

3）启动数据库

[oracle@node1 ~]$ srvctl start database -d stddb

通过node1连接：

[oracle@node1 ~]$ sqlplus '/as sysdba'

SQL*Plus: Release 11.2.0.1.0 Production on Wed May 21 19:18:37 2014

Copyright (c) 1982, 2009, Oracle.  All rights reserved.

Connected to:

Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production

With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,

Data Mining and Real Application Testing options

SQL> select instance_name,status from gv$instance;

INSTANCE_NAME    STATUS

---------------- ------------

stddb1           OPEN

stddb2           OPEN

通过node2连接：

[oracle@node2 admin]$ export ORACLE_SID=stddb2

[oracle@node2 admin]$ sqlplus '/as sysdba'

SQL*Plus: Release 11.2.0.1.0 Production on Wed May 21 19:19:53 2014

Copyright (c) 1982, 2009, Oracle.  All rights reserved.

Connected to:

Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production

With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,

Data Mining and Real Application Testing options

@至此，整个数据迁移的工作全部完成，对于单实例的原来的主库，可以继续作为备库构建容灾的环境，保护数据安全！