Backup Types

Veeam Backup & Replication uses the unstructured data backup engine to create storage snapshot-based backups of InterSystems IRIS instance data. Depending on the mode configured in the application backup policy, backup sessions produce different types of output. In snapshot-only mode, only storage snapshots are retained on the storage system. In backup mode, the policy runs as always incremental backup. The first backup session produces a full backup, and every subsequent session produces an incremental backup that transfers only the data that changed since the previous session.

Snapshot-Only Mode

In snapshot-only mode, Veeam Backup & Replication instructs the storage system to create a storage snapshot of the volumes that hold the InterSystems IRIS instance data. No data is transferred to a backup repository. Snapshots are retained on the storage system according to the snapshot retention settings configured in the policy. You can restore from a storage snapshot, but you cannot restore to a point in time between sessions.

Full Backup

Full backups contain the complete set of InterSystems IRIS instance data. The unstructured data backup engine retrieves the data from the mounted storage snapshot clone and stores it as backup data files (.vblob) in the target backup repository. The first backup policy session always produces a full backup.

Incremental Backup

Incremental backups contain only the data that changed since the previous backup. InterSystems IRIS incremental backups use a CBT (Changed Block Tracking) mechanism in the unstructured data backup engine. During each backup session, the engine reads the InterSystems IRIS instance .DAT files in 2 MB blocks, called slices in unstructured data backup terminology, and calculates a hash for each slice. The engine compares the hash to the value stored in the backup metadata from the previous session. If the hash matches, the slice is unchanged and is not transferred. If the hash differs, the engine transfers the slice and stores it as a backup data file (.vblob) in the target backup repository. Incremental backups typically take less time and require less storage space than full backups.

Only slices with a changed hash are transferred to the target backup repository.

After several backup sessions in backup mode, you have the backup data in the target backup repository, made up of the first full backup and subsequent incremental backups. Every backup session adds a restore point with a record of the InterSystems IRIS instance data at the time that backup session ran. You can use restore points to roll back the instance data to the required state.

You can restore to any available restore point that retention has not yet removed. Each restore point is self-contained and does not depend on other backup sessions being retained. For this reason, do not delete backup data manually. Veeam Backup & Replication retention removes the outdated data automatically.

For details about the backup files that Veeam Backup & Replication creates, see Backup Files.

To create backups, you must configure a protection group and an application backup policy, then run the policy. For details, see Working with Application Backup Policy.