Backup and recovery

This chapter discusses the backup and recovery strategy for an Oracle database. Based on the types of storage methods selected for the database files, there are several ways to perform a database backup. However, when using Real Application Cluster (RAC), Oracle Recovery Manager (RMAN) should be the preferred tool for backup and recovery. When database files are stored on devices configured using Automatic Storage Management (ASM), RMAN is the only method supported to back them up. RMAN is a component of the Oracle database that provides a tightly integrated method for creating, managing, restoring, and recovering Oracle database backups. This tool supports hot, cold, and incremental backups. RMAN provides an option for maintaining a repository called the recovery catalog that contains information about the backup files and archived log files. RMAN uses the recovery catalog to automate the restore operation and the media recovery. In the chapter, the backup and recovery procedures using the Enterprise Manager (EM) interface are discussed through a backup-to-disk scenario using RMAN. The concepts of target database, recovery catalog database, and media management layer are explained along with recovery features such as flash recovery, change tracking, and backup encryption.