ATION, ERROR from V$ARCHIVE_DEST where DEST_ID<=2;

Dataguard 主从切换

在 RAC 状态下，主从数据库的切换时主从库只能有一个实例在运行状态。在切换前需关掉其他节点，在切换完成后再启动其他节点。查询主从库状态

sql> select database_role,switchover_status from v$database;

将主库切换到从库状态

sql> alter database commit to switchover to physical standbywithsession shutdown;

如果主库状态为 “sessions active”，则需要在命令后加上 with sessionshutdown 语句。状态。

重起原数据库到 mount 状态。

SQL>shutdown immediate;

SQL>startup mount;

在原从库上执行切换命令

sql> alter database commit to switchover to primary withsession shutdown;

SQL>alter database open;

完成主备切换后，在新备库上启用日志应用：

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

[root@srvrac2~]# srvctl start instance -d test2 -i test22

PRCR-1013: 无法启动资源ora.test2.db

PRCR-1064: 无法在节点 srvrac2上启动资源ora.test2.db

CRS-5017:The resource action "ora.test2.db start" encountered the followingerror:

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

. Fordetails refer to "(:CLSN00107:)" in"/bee/app/11.2.0/grid/log/srvrac2/agent/crsd/oraagent_oracle/oraagent_oracle.log".

CRS-2674:Start of 'ora.test2.db' on 'srvrac2' failed

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

http://tiany.blog.51cto.com/513694/1415383

alterdatabase add logfile thread 2 ('+DATA') size 50m;

alterdatabase enable thread 2;

ORA-01092:ORACLE instance terminated. Disconnection forced

ORA-30013:undo tablespace 'UNDOTBS1' is currently in use

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

SQL>create undo tablespace undotbs2;

altersystem set undo_tablespace='UNDOTBS1' scope=spfile sid='test11';

altersystem set undo_tablespace='UNDOTBS2' scope=spfile sid='test22';

oracle单实例通过dataguard迁移到RAC(三)