Incremental backups only copy data that has changed since the last backup, making them efficient for large volumes of data. They require an initial full backup followed by subsequent incremental backups, and to restore data, all incrementals since the last full backup must be applied. Various types of incremental backups exist, including synthetic full, file-level, block-level, and byte-level incrementals, designed for different scenarios and storage systems.

1. Incremental Backup
Ferry Ananda Febian | 1912023

2. Introduction
An incremental backup is a backup type that only copies data that has been
changed or created since the previous backup activity was conducted. An
incremental backup approach is used when the amount of data that has to be
protected is too voluminous to do a full backup of that data every day. By only
backing up changed data, incremental backups save restore time and disk
space. Incremental is a common method for cloud backup as it tends to use
fewer resources.

3. How incremental backups work ?
An incremental backup scenario requires one
full backup and then subsequent incrementals
over a period of time. For example, if a full
backup was performed on Monday, Tuesday's
incremental will take a snapshot and back up all
new or changed files since Monday's backup.
However, Wednesday's incremental will only
back up files that have changed since Tuesday's
incremental backup and so on until another full
backup is performed.
To be able to restore up-to-date data or a full
copy of the data, each of the incremental
backups that were performed since the last full
backup, must be applied to that initial full
backup. It may take some time to effectively
reconstruct a new full backup to use for
disaster recovery, but ostensibly the overall
restorate process would still be faster and more
efficient that trying to do full backups on a daily
basis.

4. Common types of
incremental
backups
There are various types of incremental
backups and different scenarios for
updating data or creating new full
backups of the data. Some of these
variations include:
Synthetic full backup: A synthetic full backup is made by reading
the previous full backup and subsequent incremental backups
rather than doing another full backup that would require reading
and copying the data from the primary storage.
File-level incremental backup: A file-level incremental backs up data
on a simple, granular scale and works well with small datasets.
Block-level incremental backup: A block-level incremental is a
common form of incremental backup in which the backup software
backs up storage blocks that have been written rather than backing
up files and folders.
Byte-level incremental backup: Byte-level incremental backups are
even more granular than block-level incrementals.
Incremental forever backup: Also known as progressive
incremental backups, this variation is designed to work on disk-
based backup systems.
Enhanced incremental backup and Reverse incremental backup

5. Making an Incremental Backup
● Create one full backup
● Create two incremental backups
● Prepare the base backup
● Roll forward the base data to the first
increment
● Roll forward again to the second
increment
● Prepare the whole backup to be ready to
use

6. “That is all and thank you”
Reference :
techtarget.com/searchdatabackup/definition/incremental-backup
percona.com/doc/percona-xtrabackup/2.2/howtos/recipes_xbk_inc.html