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What are the types of backup's and what are the differences between each.

Hi,

What are the types of backup's and what are the differences between each.

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Complete backup
Differential
Incremental

REgards
Sharath
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A complete backup backs up everything no matter if the archive bit is set or not.  It then unchecks the archive bit to let windows know that this file has been backed up.
A differential backup backs up everything since the last full backup.  It does not uncheck the archive bit.
An incremental backup backus up everything since the last backup, whether that last backup was a full backup, or an incremental backup.
A full backup takes the longest time to backup, but you only have to restore the one backup.
A differential backup takes less time to backup.  To restore, you must restore the full backup and then the differential.
An incremental takes the least amount of time (typically) to backup.  To restore, you must restore the full backup AND restore every incremental backup since the last full backup.

Author

Commented:
What is the difference between Incremental and differential?
Commented:
>What is the difference between Incremental and differential?

Differential: Add anything that has changed since the last full backup.
Incremental: Add anything that has changed since the last incremental backup.

Example:

On day 1 you make a full backup.

On day 2 you change file2.txt. And then create backups like this:

differential backup: file2.txt
incremental backup: file2.txt

On day 3 you change file3.txt.

differential backup: file2.txt, file3.txt
incremental backup: file3.txt

On day 4 you change file4.txt.

differential backup: file2.txt, file3.txt, file4.txt
incremental backup: file4.txt

and so on.

Regards
Kurt
Lee W, MVPTechnology and Business Process Advisor
Most Valuable Expert 2013
Commented:
You might want to read over my backup page.  I do need to do a few minor updates, but it should probably answer most of your questions.

http://www.lwcomputing.com/tips/static/backup.asp
The differential backs up everything since the last FULL backup.  So if you created a FULL backup and then did a Differential, the Differential will backup everything that changed since that last FULL backup.  If another week goes by and you do another Differential, it will backup everything that changed since the original FULL backup including everything that was previously backed up by the first Differential.  That is why you only have to restore the FULL and the last Differential in the event of a failure.  
The Incremental only backs up data since the last backup (any backup FULL or Incremental).  So if you created a FULL backup and then did an Incremental, that first Incremental will backup everything since the FULL backup.  However, if you performed a second Incremental backup, it would only backup files that changed since the first Incremental backup.  In this case, you would have to restore the FULL backup, then the first Incremental, then the second Incremental (because the second Incremental would not have data that was backed up by the first Incremental).  You'll need to restore ALL Incremental backups (in their correct order) to restore the data.  
Another example of a total of 5 Backups
If you did 5 Full backups, you would only have to restore the last Full Backup to recover the data.
If you did 1 Full backup and 4 Differential backups for a total of 5 backups, you would have to restore the Full backup and the last Differential backup (2 restores) to recover the data.
If you did 1 Full backup and 4 Incremental backups for a total of 5 backups, you would have to restore the Full backup, plus the first, second, third and forth Incremental backups (in that order), for a total of (5 restores) to recover the data.