Expert Oracle Exadata - Parent Directory

CHAPTER 13 MIGRATING TO EXADATATransportable Tablespaces (TTS), the new Exadata database starts out as a single-instance database.Post-migration steps are needed to register the database and all its instances with Cluster Ready Services(Grid Infrastructure). Because physical migration creates an exact copy of the source database, the list ofrestrictions is very short:• The source Database version must be 11.2.This assumes that you will be migrating to Exadata V2 or X2, the old Exadata V1supports Oracle 11.1 as well.One option is to upgrade the production database to version 11.2 before copying itto Exadata. Upgrading is usually a quick process and is not dependent on the sizeof the database tables, but rather on the number of objects in the database. (Thepost-upgrade recompilation of PL/SQL packages and views may take a whilehowever.)• The source platform must be certified for running Oracle 11.2 (OEL5, RHEL5,SLES10 or other certified Linux versions).• The source platform must be little-endian (ASM rebalance and cross-platformtransportable database only). When using a hybrid solution creating a newdatabase on Exadata and using cross-platform transportable tablespaces, thesource database can be on different platforms with different endianness(supported platforms are listed in v$transportable_platform view.)There are three strategies for performing a physical migration: backup and restore, physicalstandby, and ASM rebalance. In this section we’ll discuss these strategies, how they work, and what theyare best suited for.Backup and RestoreThe backup and restore strategy uses Oracle’s Recovery Manager (RMAN) to create a full backup of thesource database and then restore it to the Exadata platform. Unless you plan to shut down the databaseduring this process, the source database must be running in Archivelog mode. The backup and restoreprocess can be done in one pass using a full backup. This is the best way to move smaller databases toExadata since smaller databases take much less time. Larger databases may take hours to backup andrestore. For these databases the process can be done in two passes by taking a full backup followed by anincremental backup.Full Backup and RestoreRMAN is used to create a full backup of the database to be migrated. The backup files are staged in a filesystem or tape library accessible to Exadata. The backup is then restored to the Exadata platform. If thesource database is on a big-endian platform, the datafiles can be converted during backup or restoreprocess using RMAN’s convert database command. The basic steps are:1. Perform pre-migration tasks:a. Create an entry in the tnsnames.ora file for your database on Exadata(optional).b. Copy the password file and parameter file (init.ora or spfile) to Exadata.452