Backup sessions

What is a backup session?

A backup session is a process that backs up data from a client system to media. A backup session always runs on the Cell Manager system. A backup session is based on a backup specification and is started when a backup is run.

During a backup session, Data Protector backs up data using default or customized behavior.

For advanced information on backup sessions, and how to control sessions, see Chapter 7 on page 219.

Object mirrors

What is an object mirror?

An object mirror is an additional copy of a backup object created during a backup session. When creating a backup specification, you can choose to create one or several mirrors of specific objects. The use of object mirroring improves the fault tolerance of backups and enables multi-site vaulting. However, object mirroring during a backup session increases the time needed for backup.

For more information, see “Object mirroring” on page 119.

Media sets

What is a media set?

The result of a backup session is backed up data on a medium or a media set. Each backup session results in one or several media sets, depending on whether you perform backup with object mirroring. Depending on the pool usage, several sessions can share the same media. When you restore data, you need to know the media from which to restore. Data Protector keeps this information in the Catalog Database.

Backup types and scheduled backups

A scheduling policy defines when backups start and the backup types (full or incremental). Consider the differences between full and incremental backups. See Table 6 on page 91.

Concepts guide

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