Disaster Recovery Overview
The first thing you should ALWAYS do when your database crashes is to make a BACKUP of your datafiles, control files, archive log files, and initialization parameters file (init.ora) for your database that crashed, either copying those files to tape or to another directory, or zipping them with something like GNU Zip, or making a tar file of them. DO NOT TRY TO RESTART YOUR DATABASE BEFORE BACKING UP THOSE FILES. Otherwise, you might make the situation worse.
After a crash occurs and you've made a backup, do a STARTUP when connected as sysdba. If there are problems encountered during startup, Oracle will display an error message about the first problem, which will usually give you an idea about what type of recovery scenario you will need to apply. In most cases, you will need to do a shutdown after this initial startup attempt before beginning the recovery.
There are three primary recovery options for media failure scenarios. The three recovery options are:
1) Database Recovery 2) Datafile Recovery 3) Tablespace Recovery
No comments:
Post a Comment