Backup Strategy: Choosing the Right Backup Type

When backup requirements are collected and data is classified, it's time to choose backup frequency and type:

✏️ Full Backup. The complete copy of data is created and sent to another location (different data center or cloud region). The approach is simple but time and resource consuming. Full backups are usually done daily or weekly

✏️ Incremental Backup. It only saves the changes made from the last backup. As data volume is relatively small, this approach is fast and consumes less storage. But recovery procedure takes more time as more backup files need to be applied: full backup + each increment. That's why it's often combined with daily or weekly full backups. Incremental backup is run every 15-60 min depending on how much data you can loose (RPO).

✏️ Differential Backup. It keeps all changes since last full backup. This type stores more data than incremental backups but recovery will be faster as only full and diff backup files will be applied. It's also used in a combination with full backups.

✏️ Forever Incremental Backups. Full backup is performed only once, then only increments are saved. To restore the data, all the incremental backups must be applied in a sequence.

✏️ Synthetic Full Backup. It's an optimization version of forever incremental backups. It combines the last full backup with recent incremental backups into a new "synthetic" full backup that speed up the recovery time.

Most cloud storages support at least full and incremental backups. Other types often depend on the backup software you’re using. When backup types and schedule are defined, you can also calculate backup storage size and costs.

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