Oracle 12c New FeaturesRecovery Manager

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Pluggable Database Support

• RMAN supports Pluggable Databases

• Back up entire Container Database or individual Pluggable Databases

• PDB point in time recovery: recover PDB individually

RMAN> alter pluggable database PLUG1 close;

RMAN> RUN {

SET UNTIL SCN 1674493;

RESTORE PLUGGABLE DATABASE PLUG1;

RECOVER PLUGGABLE DATABASE PLUG1;

}

RMAN> alter pluggable database PLUG1 open resetlogs;

Using SQL in RMAN

• No SQL prefix or quotes required

• Provides SQL*Plus DESCRIBE functionality

• Earlier releases:

RMAN> sql 'ALTER TABLESPACE users ADD DATAFILE “/testdata/users02.dbf” SIZE 10M';

• With Oracle Database 12c:

RMAN> ALTER TABLESPACE users ADD DATAFILE '/testdata/users02.dbf' SIZE 10M;

RMAN> SELECT NAME, DBID, LOG_MODE FROM V$DATABASE;

RMAN> DESC table1

Name Null? Type

--------- -------- -------------------

TEST_NAME VARCHAR2(128)

Separation of DBA Duties

Introducing task-specific and least-privileged administrative privilege

SYSBACKUP

• Includes permissions for backup and recovery (connecting to a closed

database)

• Does not include data access privileges such as SELECT ANY TABLE

• Is granted to the SYSBACKUP user that is created during database installation

• Can be explicitly used in RMAN connection by a SYSBACKUP privileged user

$ rman TARGET “john@orcl AS SYSBACKUP”

connected to target database: ORCL (DBID=1297344416)

Backing Up and Restoring Very Large Files

Multisection backups of a single data file:

• Created by RMAN, with your specified size value

• For backup sets and image copies

• For full and incremental backups

Benefits:

• Reduce image copy creation time

• Are processed independently (serially or in parallel)

• Benefit Exadata

Requirements and restrictions:

• COMPATIBLE=12.0

• Not for control files or spfiles

• Not for a large value of parallelism

RMAN> BACKUP AS COPY SECTION SIZE 1024M DATABASE;RMAN> BACKUP INCREMENTAL LEVEL 1 SECTION SIZE 1G DATABASE;

Active Duplicate Enhancements

Default use of backup sets for active duplication

• Original «push» process based on image copies becomes «pull» process based on

backup sets

• Automatic «pull» process when a clause is used:

- Compression

- Section size

- Encryption

RMAN> SET ENCRYPTION …;

RMAN> DUPLICATE TARGET DATABASE TO orcl2 FROM ACTIVE DATABASE

[USING BACKUPSET] [SECTION SIZE …] [USING COMPRESSED BACKUPSET] …;

Data is encrypted on the source database,

before transmission.

The NOOPEN Option

• Option to end database duplication with database in mounted

• Potential NOOPEN use cases:

- Avoid any startup problems: opening the database conflict with other source database

- Adjust the initialization parameters: BCT, flashback

- Moving the location of the database (for example, to ASM)

- Upgrading a database (where the database must not be open with resetlogs, prior to running upgrade scripts)

RMAN> DUPLICATE TARGET DATABASE TO ORCL12 FROM ACTIVE DATABASE NOOPEN;

Duplicating Pluggable Databases

• A single pluggable database:

RMAN> DUPLICATE DATABASE TO cdb1 PLUGGABLE DATABASE pdb1;

• Several pluggable databases:

RMAN> DUPLICATE DATABASE TO cdb1 PLUGGABLE DATABASE pdb1, pdb3;

• All pluggable databases except one:

RMAN> DUPLICATE DATABASE TO cdb1 SKIP PLUGGABLE DATABASE pdb3;

• A PDB and tablespaces of other PDBs:

RMAN> DUPLICATE DATABASE TO cdb1 PLUGGABLE DATABASE pdb1

TABLESPACE pdb2:users;

Storage Snapshot Optimization

• Take a storage snapshot using third-party technologies

• BACKUP mode is not necessary

• Point-in-Time of the snapshot can be used for recovery

• Requirements:

- The snapshot preserves the write order for each file

- The database is crash consistent during the snapshot

- The snapshot technology stores the time at which the snapshot is completed

• Structural changes during the snapshot will make the snapshots unusable

Recovering Databases with Third-Party Snapshots

• Recover a database using the most recent snapshot:RMAN> RECOVER DATABASE;

• Recover a database using a particular snapshot:RMAN> RECOVER DATABASE UNTIL TIME ‘02/15/2012 11:00:00’ SNAPSHOT TIME ‘02/15/2012 10:00:00’;

• Perform a partial recovery using archived redo log files:RMAN> RECOVER DATABASE UNTIL CANCEL SNAPSHOT TIME ‘02/15/2012 10:00:00’;

Table Recovery

• Table recovery from RMAN backups

- Not affecting the remaining database objects

- Reduces time and disk space

• Useful when you can’t use flashback

• Recover tables or table partitions

• Must connect “as sysdba” or “as sysbackup”

RMAN> RECOVER TABLE NCBSHOST.CS_TABLE UNTIL SCN 1674493 AUXILIARY DESTINATION '/tmp/oracle/recover’ DATAPUMP DESTINATION '/tmp/recover/dumpfiles’ REMAP TABLE ‘NCBSHOST'.‘CS_TABLE':‘CS_RECOVERED’;

Supported options: UNTIL TIME,

UNTIL SCN, UNTIL SEQUENCE

RMAN Recover Table: Tips

• Target database must be in READ WRITE mode

• Determine if there are dependent tables that need to be included in the recovery, based on foreign key constraints

• Ensure sufficient disk space on database server for auxiliary instance: SUM [SYSTEM, SYSAUX, UNDO, SYSEXT (if present), User Tablespace(s) that contain table(s)]

• At least one full backup has been taken of the above tablespaces, along with backup of all archived logs

• For recovering tables within a PDB, connect to CDB as ROOT user

• If source table does not exist anymore (e.g. dropped), then table and all associated indexes, constraints, triggers will also be recovered

• If source table exists, then table must be recovered with a new name (REMAP TABLE) or to a new tablespace (REMAP TABLESPACE).

RMAN Recover Table - Process

• Create a temporary auxiliary database on local database server

• Restore and recover the table or table partition

• Export the table/partition that is being recovered using the data pumps

• Optionally import and rename the table/partition in the source database

• Destroys the auxiliary database upon completion

Restore/Recover over Network

• Flexibility to restore full database, specific datafile, controlfile, spfile etc

• Using RESTORE… FROM SERVICE and RECOVER… FROM SERVICE

• Useful to fill-in the huge gap between primary and standby databases

• restore/recover a data file from standby to primary

RMAN> CONNECT TARGET “backupuser@primary_tns AS SYSBACKUP”;RMAN> RESTORE DATAFILE 9 FROM SERVICE standby_tns section size 5120M;

• Roll-forward to in-sync standby with primary

RMAN> CONNECT TARGET “backupuser@standby_tns AS SYSBACKUP”;RMAN> RECOVER DATABASE FROM SERVICE primary_tns USING COMPRESSED BACKUP;

Transporting Data Across Platforms

• Transporting databases, data files, and tablespaces

• Using image copies and backup sets

• Allows inconsistent tablespace backups

Benefits:

• Reduced down time for platform migrations

• Choice of compression and multisection

• Not catalogued in control file, not used for regular restore operations

Notes

• COMPATIBLE=12.0 (or greater)

• Read-only mode for creation of cross-platform database backup

• Database in read-write mode for creation of cross-platform tablespacebackup

• FOR TRANSPORT: backup can be transported to any destination

• TO PLATFORM: conversion performs on the source database

• DATAPUMP clause required for tablespace for last incremental backup

• RESTORE FOREIGN: restore the cross-platform data backup set

Transporting Database

• Database mode: READ_ONLY

• Back up the source database including control files

• RMAN> BACKUP FOR TRANSPORT FORMAT '/bkp_dir/transp.bck‘ DATABASE;

• RMAN> RESTORE FROM PLATFORM ‘AIX-Based Systems (64-bit)’ FOREIGN DATABASE TO NEW FROM BACKUPSET '/bkp_dir/transp.bck';

Transporting Tablespace (AIX to Linux)

On destination Linux host:

- Create ‘shell’ database (SYSTEM, SYSAUX, UNDO)

On source AIX database:

- ALTER TABLESPACE PROJECTS, TASKS READ ONLY;

- EXECUTE DBMS_TTS.TRANSPORT_SET_CHECK(PROJECTS, TASKS, TRUE)

- SELECT * FROM TRANSPORT_SET_VIOLATIONS;

- Check that user tablespaces are self-contained

- BACKUP FOR TRANSPORT FORMAT ‘/tmp/xplat_backups/trans_ts.bck’ DATAPUMP FORMAT ‘/tmp/xplat_backups/trans_ts_dmp.bck’ TABLESPACE PROJECTS, TASKS;

- Copy all backups to destination server

(cont’d)

On destination Linux database:

- Create tablespace users as they exist on source database

- RESTORE FROM PLATFORM ‘AIX-Based Systems (64-bit)’ FOREIGN TABLESPACE PROJECTS, TASKS TO NEW FROM BACKUPSET ‘/tmp/xplat_restores/trans_ts.bck’ DUMP FILE FROM BACKUPSET ‘/tmp/xplat_restores/trans_ts_dmp.bck’;

- Data file blocks automatically endian-converted during restore

- Data Pump metadata dump file automatically imported to plug in user tablespaces

- SQL> ALTER TABLESPACE PROJECTS, TASKS READ WRITE;

Demo

Recover Table Using RMAN Backupset

Oracle Database 12c