Hello All, Hope you are doing well.
Many times, We always have question in our mind that from where to start learning, when we suppose to implement a new concept, isn’t it? This article is for beginners who willing to learn RMAN in depth. In this article I am going to cover overview of RMAN, Various components of RMAN, and how to start and connect with database.
Lets begin with RMAN overviews:
RMAN stands for Recovery Manager, this is client who performs not only backup and recovery for oracle database but also making DBA’s life easier in terms of automation, backup, restore and recovery of database. RMAN consist of some backup utilities and collaborated with your oracle database that combine play a role in database backup.
Target database is the registered database with the RMAN, on which RMAN is performing backup and recovery operations. All operations performed and practiced ( i.e.metadata is also known as repository. ) by RMAN would be logged in database control file.
RMAN client is nothing but the executable required to run RMAN and performers its desire task. RMAN client situated in ‘ORACLE_HOME/bin’. No extra efforts would be required to install this client, because this client installed automatically when oracle software being installed.
RMAN Optional components are as follows:
Fast Recovery Area:
Fast Recovery Area also called as FRA, this is nothing but the disk location where database can stored and manage files regarding backup and recovery. We can control FRA by specifying its location and size according to user’s convenience.
Media manager is responsible in making communication between RMAN client and media like tape, etc. It also responsible for managing media while backup and recovery, media loading, media labeling and unloading.
Recovery catalog is one of the database schema, who holds all RMAN activity of one or more target databases.
There is a risk involved in losing all RMAN repository metadata while loss of controlfile. But with the help of recovery catalog we can reatain it.
In case of loss of database controlfile there is a risk to loss of all RMAN repository metadata.
Recovery catalog don’t overwrite older records but control file do by the time goes on.
Lets do some practical, Starting RMAN and connecting to your database.
To start RMAN, we need to instantiate RMAN client by RMAN command on OS prompt:
[root@ol11g ~]# su - oracle -bash-4.1$ rman Recovery Manager: Release 220.127.116.11.0 - Production on Fri Oct 6 22:13:05 2006 Copyright (c) 1982, 2009, Oracle and/or its affiliates. All rights reserved. RMAN>
Note: Above, we considered oracle environmental variables already set. ( ‘ORACLE_HOME’, ‘ORACLE_SID’ and ‘PATH’ )
To connect target database, issue the command “connect target /” on RMAN prompt with the help of OS authentication.
RMAN> connect target / connected to target database: GALAXY (DBID=3647455456)
Note: GALAXY is my target database & 3647455456 is its Database ID.
We can also connect to target database with the help of user authentication:
RMAN> connect target system@galaxy connected to target database: GALAXY (DBID=3647455456)
To quite from RMAN prompt, simply write ‘exit’ on RMAN prompt:
These is all about Overview, components of RMAN and starting RMAN and connecting with database.
In my next article, I will explain how to backup database with the help of RMAN backup utility in Archive log and NoArchive log mode.
Stay tune. 🙂