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Recover Lost Control File -Exercise

Objective: Practice recovering a lost control file.

This exercise uses a Slide Show to allow you to simulate a sequence of procedures.

Background/overview

Suppose a media failure destroyed all your control files. Fortunately, you made a backup of the control file via the
ALTER DATABASE BACKUP CONTROLFILE TO 
'C:\ORANT\DATABASEx\BACKUPORCL\CTL1ORCL_f.ora';
a couple of days ago. Now you have to use this copy of the control file to recover the lost control file and start the system.

Instructions

This simulation gives you a chance to practice the steps of recovering a lost control file. When you are finished, click the Submit button to receive credit for completing the exercise. Since your backup control file is made through the ALTER DATABASE BACKUP CONTROLFILE TO <file_name>; command, you have to:
  1. Restore this control file
  2. Mount the database
  3. Issue the ALTER DATABASE BACKUP CONTROLFILE TO TRACE; command
  4. Recreate the control file
Unlike most simulations within this course, there are a few steps you'll need to figure out on your own.
We will tell you what to do, but figuring out how to do it will be your task in this exercise.
  1. To make sure you point to the right database ORCL, you need to set the ORACLE_SID. Type the command at the prompt and press Enter.
  2. SET ORACLE_SID=ORCL
  3. Try typing |||(S1)SET ORACLE_SID=ORCL|||(S0) at the prompt.
  4. You need to restore the backup control file. Suppose that the backup control file is located at
    C:\ORANT\DATABASEx\ORCLBACKUP\CTL1ORCL_f.ora 
    
    and your working directory is
    C:\ORANT\DATABASE\. 
    
    Type the command at the prompt and press Enter.
  5. COPY C:\ORANT\DATABASEx\ORCLBACKUP\CTL1ORCL_f.ORA C:\ORANT\DATABASE\CTL1ORCL.ORA
  6. Try typing |||(S1)COPY C:\ORANT\DATABASEx\ORCLBACKUP\CTL1ORCL_f.ORA C:\ORANT\DATABASE\CTL1ORCL.ORA|||(S0) at the prompt.
  7. You need to access Server Manager. Type the command at the prompt and press Enter.
  8. SVRMGR30
  9. Try typing |||(S1)SVRMGR30|||(S0) at the prompt.
  10. Now you are ready to connect as sysdba. Type the command at the prompt and press Enter. (The password ORACLE is entered for you.)
  11. CONNECT INTERNAL
  12. Try typing |||(S1)CONNECT INTERNAL|||(S0) at the prompt.
  13. You need to mount the database with the backup control file. Type the command at the prompt and press Enter.