As a Linux sysadmin, you might recover a system from backup, which may include Oracle Database.
So, it is essential for all admins to understand how to restore oracle database from backup.
Typically, DBAs will use Oracle RMAN utility to take a hot backup of the database.
This tutorial provides an introduction on how to restore an Oracle database on a Linux server from RMAN backup.
http://www.thegeekstuff.com/2014/11/oracle-rman-restore/
