Or, Understanding
Windows backups types and concepts
Or, Different types
of backups and restore methods used in backup technologies
Or, How many types of
backups are and how restoration works
Descriptions: If
you are new to backup administration and want to understand the fundamentals of
different backup types and use cases, this article is for you. Guys,
technically for Backup Administrators, there are three types of backup Full, Differential and Incremental but generally
there are five type of backups as shown below.
1. Full or Normal Backup
2. Incremental Backup
3. Differential Backup
4. Copy Backup
5. Daily Backup
Full Backup: Full
backup contains full data. Whenever you run Full backup, it takes backup of all
selected files and folders every time. This type of backup consumes more disk
space and takes longer time to complete.
Example: If you
have schedule “Full Backup” to be executed on Monday of every week and total
data size of the selected files/folders is 100GB, then every week you need
100GB of HDD space or tape media space to store this backup data.
Note: To restore
complete data from full backup, you need only last recent “Full Backup” set.
Differential Backup:
Diff backup contains only those data which was modified or created after “Full
Backup”. Every time you run differential
backup, it compares itself with last recent full backup and backs up only those
files/folders that was modified or created after last recent full backup.
Example: Your last
full backup was completed on Monday with 100GB backup data and your next diff
backup is scheduled to be executed on next Sunday. So, in next diff backup,
only those files and folders will be backed up which has been modified or
created after last full backup (Monday) and before diff backup execution
(Sunday). Suppose only 2 GB of data was
modified after full backup, so in this diff backup only 2GB of data will be
backed up not 102GB (100GB+2GB).
Note: To restore
data from “Full Backup” + “Diff Backup” scenario, you have to have one set of
last recent full backup and last recent “Diff backup”.
Incremental Backup: Incremental backup contains only those data
which was modified or created after full backup but in separate backup sets.
Every time you run incremental backup, it compares itself with its last backup
(whether is it full or incremental).
Example: If your
last full backup was completed on Monday with 100GB backup data and your next
incremental backup is scheduled to be executed on next Sunday. So, in next
incremental backup, only those files and folders will be backed up which has
been modified or created after last backup full/incremental backup. Suppose only 2 GB of data was modified after
full backup, so in this First incremental backup only 2GB of data will be
backed up not 102GB (100GB+2GB).
Next incremental backup will be backing up only those data
which would be modified or created after last incremental backup. Means, if
data modified between last incremental backup is upcoming incremental back is
only 3GB, then the upcoming incremental backup will have only 3GB data backup.
Note: To restore
complete data from “Full Backup” + “Incremental Backup” Scenario, you have to
have Last recent full backup and all incremental backup sets with you. This backup combination consumes lesser disk
or tape space and take lesser time to complete but complex to restore.
Daily Backup:
When you simply copy files/folders to a different location rather than original
on daily basis, is called daily backup.
Copy Backup: when
you simply copy your files/folder to different location rather than original on
your need basis, is called copy backup.
Cheers, Please write me back if you have any query on this.