Veritas NetBackup™ for DB2 Administrator's Guide

Snapshot backup

A snapshot backup occurs when NetBackup and DB2 coordinate to create a point-in-time disk image of the database for backup. This process is nearly instantaneous; so user access to the database is not interrupted during the backup. The snapshot can then be backed up to storage and or retained for instant recovery.

Instant recovery

This feature enables instant recovery of the database from a previously created snapshot. It combines snapshot technology with the ability to do rapid disk-based restores.

Off-host backup

The off-host backup shifts the burden of reading the snapshot to a separate host. The database host is only involved in performing the snapshot. The snapshot is mounted, read, and transferred to storage by either an alternate client, the media server, or a third-party copy device.

Block-level incremental backup

Available only on UNIX, a Block-Level Incremental (BLI) Backup uses the change tracking capabilities of the Veritas File System (VxFS) Storage Checkpoint feature. In a BLI backup, only the changed file system blocks are backed up, not the entire file or file system. A BLI backup saves time, decreases the amount of backup media that is required, and significantly reduces CPU and network overhead during backups.

Proxy operations

A proxy backup or restore is a special type of operation where DB2 does not read or write the database files. Instead, NetBackup for DB2 acts as a proxy and performs all of the data movement. NetBackup coordinates with DB2 to ensure that the correct files are in the correct state for the operation.

Snapshot, BLI backups, and Instant Recovery are examples of proxy operations.

Backups and restores remain tightly integrated with DB2 and its catalog, greatly simplifying administration tasks.

File-based operations

DB2 provides the list of files that require backup or restore to NetBackup for DB2 with Snapshot Client. It then acts as a proxy to perform the data movement.

Snapshot backups and user-exit log archiving are examples of file-based operations.

More information is available.

See NetBackup for DB2 file-based operations.

Stream-based operations

Stream-based is the conventional DB2 database backup method. DB2 reads the files that require backup and provides a stream of buffers containing the contents to NetBackup for DB2. NetBackup transports the buffers to storage. At restore time, DB2 requests the return of the buffers and then writes them back onto the disk where the database resides.

Database backups that do not use snapshots and vendor log archiving are examples of stream-base operations.

More information is available.

See NetBackup for DB2 stream-based operations.

bpdb2proxy

This NetBackup for DB2 command is used in backup and restore scripts to initiate snapshot backup and restore.

NetBackup for DB2 wizards

The templates that the wizard creates, automatically initiate snapshot operations if the policy is configured for snapshots.