Dell NetWorker 19.9 Administration Guide

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Comparing backup levels

Evaluate the advantages and disadvantages of each backup level to develop the backup strategy for an environment.

The following table lists key advantages and disadvantages of each backup level.

Table 1. Advantages and disadvantages of backup levels
Backup level	Advantages	Disadvantages
Full	Faster recovery	Slower backups High server load High load on the client and network Uses more volume space
Incremental	Faster than a full backup Low server load Uses less volume space than a full backup	Slow recovery Data can spread across multiple volumes
Cumulative incremental	Faster than a full backup Low server load Uses the least amount of volume space	Slow recovery Data can spread across multiple volumes
Logs only	Faster than a full or incremental backup Low server load	Slow recovery Data can spread across multiple volumes
Synthetic full	Faster than a full backup Faster recovery Low load on the server, client, and network Requires fewer volumes for recovery	High load on the storage node Requires at least two volume drives Uses the most volume space

Review the following additional considerations when selecting backup levels:

If you have only one stand-alone storage device and the full backup does not fit on a single piece of media, an operator must be available to monitor the backup, and change the media.
Full backups cause the online indexes to grow more rapidly than incremental or cumulative incremental backups.
Cumulative incremental backups serve as checkpoints in schedules because they collect all the files that have changed over several days, or even weeks, into a single backup session.
Synthetic full backups provide the same benefits at the same cost as full backups. The difference is that synthetic full backups are less taxing on the network and client because a new full backup is created from a previously created full or synthetic full backup and subsequent incremental backups.