Cross-Platform Transportable Database: RMAN CONVERT DATABASE

The RMAN CONVERT DATABASE command is used to automate the movement of an entire database from one platform (the source platform) to another (the destination platform). Provided that the source and destination platforms are of the same endian format, RMAN automates most of the steps of creating a new database on the destination platform, which contains the same data as the source database, and which has, with a few exceptions, the same settings as the source database.

The CONVERT DATABASE command is one step in a longer process for transporting databases across platforms, which is described in the following sections. As with transporting tablespaces, the RMAN CONVERT DATABASE step in the process can be performed either on the source platform or the destination platform. The overall transport process changes depending upon whether you perform the CONVERT DATABASE step on the source or destination platform.

Files automatically transported to the destination platform during cross-platform database transport include:

Datafiles that belong to permanent tablespaces.

Note:

In spite of the fact that the endian formats for the source and destination platform are the same, the datafiles for a transportable database must undergo a conversion process and cannot simply be copied directly from one platform to another, as is possible with transporting tablespaces.

Unlike transporting tablespaces across platforms, transporting entire databases requires that certain types of blocks, such as blocks in undo segments, be reformatted to ensure compatibility with the destination platform.

If a PFILE is used, it is transported. If an SPFILE is used, a PFILE is generated based on the SPFILE and transported, and a new SPFILE is created at the destination based on the settings in the PFILE.

Note:

In most cases, some parameters in the PFILE require manual updating for the new database. For example, you may change the DB_NAME, as well as parameters such as CONTROL_FILES that indicate the locations of files on the destination host.

This section contains the following topics:

Restrictions on Cross-Platform Transportable Database

The principal restriction on cross-platform transportable database is that the source and destination platform must share the same endian format. For example, while you can transport a database from Microsoft Windows to Linux for x86 (both little-endian), or from HP-UX to AIX (both big-endian), you cannot transport a whole database from HP_UX to Linux for x86 using this feature. You can, however, create a new database on a destination platform manually, and transport needed tablespaces from the source database using cross-platform transportable tablespace as described in "Cross-Platform Tranportable Tablespace: CONVERT DATAFILE or TABLESPACE".

Also note that some parts of the database cannot be transported directly:

Redo log files and control files from the source database are not transported. New control files and redo log files are created for the new database during the transport process, and an OPEN RESETLOGS is performed once the new database is created.

Note:

The control file for the converted database does not contain a copy of the RMAN repository information from the source database. Backups from the source database cannot be used with the converted database.

BFILEs are not transported. RMAN provides a list of objects using the BFILE datatype in the output for the CONVERT DATABASE command, but users must copy the BFILEs themselves and fix their locations on the destination database.
Tempfiles belonging to locally managed temporary tablespaces are not transported. The temporary tablespace will be re-created on the target platform when the transport script is run.
External tables and directories are not transported. RMAN provides a list of affected objects as part of the output of the CONVERT DATABASE command, but users must redefine these on the destination platform. See Oracle Database Administrator's Guide for more information on managing external tables and directories.
Password files are not transported. If a password file was used with the source database, the output of CONVERT DATABASE includes a list of all usernames and their associated privileges. Create a new password file on the destination database using this information. See Oracle Database Security Guide for more information on managing password files.