How to multiplex or move controlfile and Redolog files across diskgroups
Hi All,
you may face a situation where you have to multiplex controlfile across multiple diskgroups especially after the database is created.However with ASM this activity is not simple enough just as in filesystem when we simply copy files from one folder/directory to another and edit the init.ora.
I assume you are using OMF feature by setting db_create_file_dest
In order to multiplex/move teh controlfile to different diskgroup use the following command
Database Instance
SQL> alter database backup controlfile to ‘+DB_DSK_GRP2′;
this will create backup controlfile in the diskgroup +DB_DSK_GRP2
c:\> set oracle_sid=+asm
C:\>asmcmd
ASMCMD> cd +DB_DSK_GRP2/test/control
ASMCMD> ls
backup.256.47238470
ASMCMD> mkalias backup.256.47238470 control02.ctl
SQL> show parameter control_files;
Name Value
————————————————————————————–
control_files +DB_DSK_GRP1/test/control/control.256.5689371
SQL> alter system set control_files=’+DB_DSK_GRP1/test/control/control.256.5689371′,’+DB_DSK_GRP2/test/control/control02.ctl’ scope=spfile
To multiplex redo log across diskgroups perform the following steps
SQL> alter database add logfile member ’+DB_DSK_GRP2′ to group 1;
SQL> alter database add logfile member ’+DB_DSK_GRP2′ to group 2;
SQL> alter database add logfile member ’+DB_DSK_GRP2′ to group 3;