Sections of Control File

1.Non Reusable Section

2.Reusable Section

 

Reusable section of the control file contains RMAN backup info.Since control file is one of the

important file, it is recommanded to mirror/multiplex to avoid single point of failures.

 

If the control file is lost, we cannot mount the database. If the control file is lost during the

operations of the database, database will not function.

 

To avoid single point failures, recommanded to mirror, but see that mirrored copies resides in a

separate file system.

 

If all the control files are lost, we need to restore the control files from the backup and we need

to perform recovery.

 

Whenever we create a new tablespace or add a new datafile, it is going to change the structure of

the control file(adding new redo log group or dropping a member also does that).

 

Whenever we change the structure of the control file, recommanded to issue the fillowing command :

                SQL> alter database backup controlfile to trace;

The above command creates a text based control file in "udump" directory or "diagnostic_dest"

location.

 

If we want to change the name of the database, we need to change the database name in the Pfile as

well as in the control file by recreating the control file.

 

Maximum we can maintain upto 8 control files.