RMAN an introduction
RMAN (Recovery Manager) recovery is based on SCN ( system change numbers) - they are an expression of linear date time expressions. They are also called technically the change vectors. which represents the time and transaction. The transaction means
1. internal (recursive call) transactions also building metadata.
2. application data transactions occupying the storage with the DML statements.
RMAN Backup Concepts
RMAN Backup Concepts (source Oracle)
Media Recovery enabled - RPO and RTO can be implemented.
Media Recovery disabled - RPO and RTO are irrelavent.
Backup can be taken using RMAN in those two states. Media Recovery Enabled (database in archivelog mode) and Media Recovery Disabled (database in noarchivelog mode).
BackingUpTheDatabase
Backing Up the Database (Source Oracle)
Use the BACKUP command to back up all or part of your database.
Backing Up the Database: Advanced Topics to learn about more advanced topics such as backup optimization, duplexing, backup encryption, and restartable backups
Oracle Data Guard Concepts and Administration to learn how to perform RMAN backup and recovery in a Data Guard environment
OracleFlashback
Oracle Database includes the following logical flashback features:
Oracle Database includes the following logical flashback features:
Oracle Flashback Query
You can specify a target time and run queries against a database, viewing results as they would appear at the target time. To recover from an unwanted change like an update to a table, you could choose a target time before the error and run a query to retrieve the contents of the lost rows. Oracle Database Development Guide explains how to use this feature.
Purpose of Backup and Recovery
1. Oracle Backup and Recovery Solutions
Purpose of Backup and Recovery:
As a backup administrator, your principal duty is to devise, implement, and manage a backup and recovery strategy. In general, the purpose of a backup and recovery strategy is to protect the database against data loss and reconstruct the database after data loss. Typically, backup administration tasks include the following:
RMAN Environment
RMAN Environment
Recovery Manager (RMAN) is an Oracle Database client that performs backup and recovery tasks on your databases and automates administration of your backup strategies. It greatly simplifies backing up, restoring, and recovering database files.
Rman at work
Connecting to RMAN with "NOCATALOG" and "CATALOG"
"rman" client application can be opened directly from command prompt
c:\Oracle\bin>set ORACLE_SID=srinivas
c:\Oracle\bin>echo %ORACLE_SID%
srinivas
c:\Oracle\bin>rman
RMAN Troubleshooting
Troubleshooting RMAN
Run the following command to find if RMAN sessions exist in the database instance (format the output for readability):
SELECT p.SPID,
s.EVENT,
s.SECONDS_IN_WAIT AS SEC_WAIT,
sw.STATE,
s.CLIENT_INFO
FROM V$SESSION_WAIT sw,
V$SESSION s,
V$PROCESS p
WHERE sw.EVENT LIKE '%Backup%'
AND s.SID=sw.SID
AND s.PADDR=p.ADDR;
Oracle SW installation
Installing the Oracle Database Software on the Destination Host
When the source and destination host are different, you must install the Oracle Database software on the destination host, so that the auxiliary instance can be created.
Note:
Ensure that you install the same release of Oracle Database software, with the same patch level, on both the source and destination host.
Duplicating database prerequisites
Naming Duplicate Database Files
When you duplicate a database, RMAN generates names for the database files in the duplicate database. This includes the control files, data files, temp files, and online redo log files.
Depending on your duplication scenario, you can name the duplicate database files by using one of the following techniques:
a. Using the Same Names for Database Files in the Source Database and Duplicate Database
b. Using Different Names for the Database Files in the Source Database and Duplicate Database
Naming Duplicate datafile names
Naming Duplicate Database Files
When you duplicate a database, RMAN generates names for the database files in the duplicate database. This includes the control files, data files, temp files, and online redo log files.
Depending on your duplication scenario, you can name the duplicate database files by using one of the following techniques:
a. Using the Same Names for Database Files in the Source Database and Duplicate Database
b. Using Different Names for the Database Files in the Source Database and Duplicate Database
Example scripts for duplicate
edit tnsnames.ora on the remote host where binaries were cloned and network assistant configured listener is configured.
dupdb = (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=dup.example.com)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=dup)))
srcdb = (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=src.example.com)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=src)))
RMAN Choosing A Duplication Technique
Choosing a Duplication Technique
Your business requirements and the database environment determine which duplication technique is best for your situation.
RMAN Preparing The Auxiliary Instance
Preparing the Auxiliary Instance
RMAN uses an auxiliary instance to create the duplicate database. You must prepare the auxiliary instance before you begin the duplication.
Depending on your duplication scenario, you need to perform either some or the tasks that are described in this section. Preparing the auxiliary instance includes the following tasks....
RMAN Duplicating The Whole Database
Choosing a Duplication Technique
Your business requirements and the database environment determine which duplication technique is best for your situation.
RMAN Duplicating CDBs And PDBs
Duplicating CDBs and PDBs
(source Oracle Docs)
Use the DUPLICATE command to duplicate CDBs, one or more PDBs, sparse CDBs, and sparse PDBs. The steps to duplicate CDBs and PDBs are similar to those of duplicating non-CDBs with minor variations to the procedure for duplicating a non-CDB. This section describes how to duplicate CDBs and PDBs.
RMAN Duplicating Sparse PDBs
Duplicating CDBs and PDBs
(source Oracle Docs)
Use the DUPLICATE command to duplicate CDBs, one or more PDBs, sparse CDBs, and sparse PDBs. The steps to duplicate CDBs and PDBs are similar to those of duplicating non-CDBs with minor variations to the procedure for duplicating a non-CDB. This section describes how to duplicate CDBs and PDBs.
RMAN Duplicating Databases To OracleCloud
Duplicating Databases to Oracle Cloud
(Source: Oracle Docs)
Use the DUPLICATE command to duplicate an on-premise database to Oracle Cloud.
Both backup-based and active duplication are supported.
Oracle databases on Oracle Cloud are always encrypted.
Duplicating an Oracle Cloud Database as an On-premise Database
Duplicating an Oracle Cloud Database as an On-premise Database
(Source: Oracle Docs)
Use the DUPLICATE command to duplicate an Oracle Cloud Database as an on-premise database. Both backup-based and active duplication are supported.
RMAN Restarting DUPLICATE After A Failure
Restarting DUPLICATE After a Failure
(Source: Oracle Docs)
RMAN automatically optimizes a DUPLICATE command that is a repeat of a previously failed DUPLICATE command.
The repeat DUPLICATE command notices which data files were successfully copied earlier and does not copy them again...
RMAN Duplicating Databases
Duplicating Databases
=====================
This chapter contains the following topics:
Specifying Alternative Names for Duplicate Database Files
Making Disk Backups Accessible Without Shared Disk....
RMAN Creating Transportable Tablespace Sets
Overview of Creating Transportable Tablespace Sets
(Source: Oracle Docs)
We can use RMAN or the transportable tablespaces feature to create transportable tablespace sets.
Purpose of Creating Transportable Tablespace Sets...
RMAN ENHANCEMENTS
RMAN ENHANCEMENTS
Oracle 12c New Features 07 – RMAN Enhancements
SrinivasMaddali
RMAN Enhancements
The following sections describe improvements to Recovery Manager (RMAN).
RMAN LIST COMMAND USAGE
RMAN LIST COMMAND USAGE
The LIST command allows the backup data to be listed in the RMAN utility
Database
To list all existing backups use:
LIST BACKUP
CONNECTIVITY
CONNECTIVITY
RMAN Connectivity and default database backup
Connect to RMAN take backup.
Using NOCATALOG, which is the default method of connecting to RMAN, one can connect using operating system authentication or Oracle Net Authentication.
RMAN RECOVER MANAGER ORACLE
RMAN (Recovery Manager) is a backup and recovery manager supplied for Oracle databases (from version 8) created by the Oracle Corporation. It provides database backup, restore, and recovery capabilities addressing high availability and disaster recovery concerns.