20 Backing Up and Recovering CDBs and PDBs
You can back up and recover multitenant container databases (CDBs) and pluggable databases (PDBs).
This section contains the following topics:
- Overview of Backing Up and Recovering CDBs and PDBs
When using the multitenant architecture, you can perform backup and recovery operations on a whole multitenant container database (CDB), the root, or one or more pluggable databases (PDBs). - Backup and Complete Recovery of CDBs
To perform backup and complete recovery operations on a whole multitenant container database (CDB), you connect asTARGET
to the root. - Backup and Complete Recovery of PDBs
You can perform backup and complete recovery operations on a single pluggable database (PDB) or on multiple PDBs. - Point-in-Time Recovery in a Multitenant Environment
You can perform point-in-time recovery of the whole multitenant container database (CDB) or a particular pluggable database (PDB). - Flashback Database in a Multitenant Environment
You can perform a Flashback Database operation for a whole multitenant container database (CDB) or for a particular pluggable (PDB).
Parent topic: Using Oracle Features in a Multitenant Environment
20.1 Overview of Backing Up and Recovering CDBs and PDBs
When using the multitenant architecture, you can perform backup and recovery operations on a whole multitenant container database (CDB), the root, or one or more pluggable databases (PDBs).
The Oracle Recovery Manager (RMAN) commands used to backup and recover CDBs and PDBs are the same as those used for non-CDBs, with minor variations in the syntax. The backup and recovery operations performed on non-CDBs can also be performed on CDBs and PDBs. This includes the following:
-
Full and incremental backups
-
Complete and point-in-time recovery (PITR)
-
Flashback Database
-
Reporting operations (such as listing backups and cross-checking backups)
About Connecting to CDBs and PDBs
You can connect to the root in one of the following ways:
-
Connect using operating system authentication
You are connected to the root as the
SYS
user with theSYSDBA
privilege. -
Connect locally as a common user
-
Connect as a common user through Oracle Net Services
To connect as TARGET
to a PDB, use one of the following techniques:
-
Connect with a net service name that resolves to a database service for that PDB
-
Connect locally as a common user or local user with the
SYSDBA
orSYSBACKUP
privilege
Note:
Certain operations are not available when you connect directly to a PDB. See Oracle Database Backup and Recovery User’s Guide for a list of these operations.
See Also:
The following sections in the Oracle Database Backup and Recovery User’s Guide provide detailed information about backing up and recovering PDBs:
Parent topic: Backing Up and Recovering CDBs and PDBs
20.2 Backup and Complete Recovery of CDBs
To perform backup and complete recovery operations on a whole multitenant container database (CDB), you connect as TARGET
to the root.
The connection must be established as a common user with the SYSDBA
or SYSBACKUP
privilege.
After you connect to the root, the same commands that are used to perform operations on non-CDBs are used to perform backup and complete recovery on the entire CDB.
See Also:
The following sections in the Oracle Database Backup and Recovery User’s Guide provide detailed information about performing backup and complete recovery of CDBs:
Parent topic: Backing Up and Recovering CDBs and PDBs
20.3 Backup and Complete Recovery of PDBs
You can perform backup and complete recovery operations on a single pluggable database (PDB) or on multiple PDBs.
Backups of PDBs
When relocating a PDB or cloning a non-CDB as a PDB, you may want to retain the use of preplugin backups. For preplugin backups to be usable in the destination CDB, metadata about the preplugin backups must be exported to the RMAN repository of the destination CDB.
The technique for making the backups usable depends on the type of operation:
-
Creating a PDB by cloning a non-CDB
When the non-CDB is opened in read/write mode, you must execute the
DBMS_PDB.EXPORTRMANBACKUP
procedure as the last step before cloning. When plugging in the non-CDB as a PDB to a destination CDB, the operation copies the backup metadata of the source non-CDB into the data dictionary of the destination CDB. -
Relocating a PDB to another CDB
When you unplug the source PDB, the backup metadata is automatically exported. Therefore, you do not need to execute
DBMS_PDB.EXPORTRMANBACKUP
.
Preplugin backups are usable only on the destination CDB into which you plug in the source non-CDB or PDB.
Note:
-
Oracle Database Backup and Recovery User’s Guide to learn about preplugin backups
-
Oracle Database Backup and Recovery User’s Guide to learn how to create a preplugin backup of the whole database
-
Oracle Database PL/SQL Packages and Types Reference to learn more about the
DBMS_PDB.EXPORTRMANBACKUP
procedure
Syntax for Backup Commands
Although the Oracle Recovery Manager (RMAN) commands are the same, the syntax used to perform operations on multiple PDBs contains some modifications.
To perform backup and complete recovery operations on a single PDB, you can connect as TARGET
to either of the following containers:
-
PDB
In this case, use the same commands that you would use to backup or recover non-CDBs. For example, to back up a PDB, use the
BACKUP DATABASE
command. -
CDB$ROOT
In this case, use the
PLUGGABLE DATABASE
clause in your RMAN commands. The following command backs up the PDBhrpdb
when connected to the root:BACKUP PLUGGABLE DATABASE hrpdb;
To perform backup and complete recovery operations on multiple PDBs using a single command, you must connect to the root. Use the
PLUGGABLE DATABASE
clause followed by the list of PDBs on which you want to perform the operation. The following example backs up the PDBshrpdb
,salespdb
, andinvpdb
when connected to the root:BACKUP PLUGGABLE DATABASE hrpdb, salespdb, invpdb;
See Also:
The following sections in the Oracle Database Backup and Recovery User’s Guide provide detailed information about backing up and recovering PDBs:
Parent topic: Backing Up and Recovering CDBs and PDBs
20.4 Point-in-Time Recovery in a Multitenant Environment
You can perform point-in-time recovery of the whole multitenant container database (CDB) or a particular pluggable database (PDB).
Point-in-Time Recovery of a CDB
To perform point-in-time recovery of a CDB, you must meet the following prerequisites:
-
You must be logged in to the root container as a common user with the
SYSDBA
orSYSBACKUP
privilege. -
The CDB must be mounted.
When performing the recovery operation, use the same commands that you use for non-CDBs.
Point-in-Time Recovery of a PDB
When a PDB is closed in an open or closed CDB, you can recover the PDB to a past point in time. The technique depends on the undo mode of the CDB. The following table describes the differences.
Table 20-1 Differences in Point-in-Time Recovery Techniques
Undo Mode | Auxiliary Instance Used? | Connect as TARGET to ... | RMAN Commands to Use for Recovery |
---|---|---|---|
Shared |
Yes |
CDB root |
Include the RMAN uses an auxiliary destination to store temporary files created during recovery. If a fast recovery area has been configured, then it is used as the auxiliary destination. You can explicitly specify an auxiliary destination using the |
Local |
No |
CDB root or PDB |
When connected to the PDB, use the same commands that you use for non-CDBs. When connected to the root, include the |
See Also:
The following sections in the Oracle Database Backup and Recovery User’s Guide for more information about point-in-time recovery.
Parent topic: Backing Up and Recovering CDBs and PDBs
20.5 Flashback Database in a Multitenant Environment
You can perform a Flashback Database operation for a whole multitenant container database (CDB) or for a particular pluggable (PDB).
RMAN uses an auxiliary destination to store temporary files created during point-in-time recovery. By default, the fast recovery area is used as the auxiliary destination. You can explicitly specify an auxiliary destination using the AUXILIARY DESTINATION
clause in the RECOVER
command.
Flashback of CDBs
To perform Flashback Database for a CDB, you must meet the following prerequisites:
-
You must be connected to the root as a common user with the
SYSDBA
orSYSBACKUP
privilege. -
The CDB must be mounted.
Specify the target point in time for the flashback operation using a CDB restore point, time expression, or SCN. A CDB restore point is accessible to every PDB within the CDB. However, the restore point does not reflect the PDB sub-incarnation of any of its PDBs.
Flashback of PDBs
When a PDB is closed and the CDB is open, you can perform a flashback database operation for this PDB using the FLASHBACK DATABASE
command. Performing a Flashback Database operation on a particular PDB modifies only data files related to that PDB. The other PDBs in the CDB are not impacted and are available for use. Note that a PDB restore point is accessible only to the PDB in which it is defined and can be used for operations only on this PDB.
Table 20-2 Differences in Flashback Techniques
CDB Undo Mode | Auxiliary Instance Used? | Connect as TARGET to ... | Commands |
---|---|---|---|
Shared |
Yes |
CDB root |
Use the RMAN uses an auxiliary destination to store temporary files created during flashback. If a fast recovery area has been configured, then it is used as the auxiliary destination. You can explicitly specify an auxiliary destination using the |
Local |
No |
CDB root or PDB |
Use the |
See Also:
The following sections in the Oracle Database Backup and Recovery User’s Guide for more information about flashback of CDBs and PDBs:
Parent topic: Backing Up and Recovering CDBs and PDBs