The great thing about incremental backups is that each individual backup is small. Since only differences from the last backup are copied, the backup process requires relatively little time, bandwidth and storage space. The prerequisite for this is that the period between each individual backup remains short. Otherwise, large volumes of data accumulate and must be transferred.
The inherent advantage of incremental backups is best illustrated by the term “backup window”. This is the period during which a backup can be created without disrupting the proper functioning of the system. If the amount of data is such that the copy process would take longer than the backup window allows, it becomes unable to create a full backup when the system is in use. In this case, it is advisable to create small incremental backups at short intervals.
The immediate downside of incremental backups is the fact that a specialized software is usually required. Planning the backup strategy also requires more effort than creating full backups. The same goes for restoring the original state from backups. The data being scattered across multiple backups, the process is more complex. There is also a higher risk of data loss. If an incremental backup within a chain is damaged, the integrity of all subsequent backups will be impacted.
