Does differential backup remove deleted files/folders?

Discussion in 'Acronis True Image Product Line' started by Hans L, Jan 7, 2009.

Thread Status:
Not open for further replies.
  1. Hans L

    Hans L Registered Member

    Joined:
    Dec 26, 2006
    Posts:
    30
    I think I saw something about this in the documentation earlier, but now, I cannot find it. So, let me ask:

    Does a differential backup not only add new files and folders, but does it also remove deleted files and folders?

    Regards,

    Hans L
     
  2. seekforever

    seekforever Registered Member

    Joined:
    Oct 31, 2005
    Posts:
    4,751
    Yes. Consider that a file is present when the full backup is made and then the file is deleted and then a differential is made. When the full is restored the file will be restored and will be on the HD but after the differential is restored it will be deleted to reflect the state of the computer when the differential was made.

    Same for incrementals. The idea is always to restore the HD to the state when the last restored backup was made.
     
  3. Hans L

    Hans L Registered Member

    Joined:
    Dec 26, 2006
    Posts:
    30
    Thank you, seekforever. However, may I ask you, just to be sure I understand this okay, what do you mean by "restored".

    ("When the full is restored the file will be restored and will be on the HD but after the differential is restored it will be deleted to reflect the state of the computer when the differential was made.")

    Why does the full file need to be restored? If I read the Help file correctly, first, a full backup is created, and when a differential backup is created, it modifies the full backup to reflect changes (added and deleted files and folders).

    Next time, the new (not restored) backup (mix of full and differential backup) is modified by the next differential backup, and a new (not restored) backup is created.

    So, where does the "restore" come in?

    Thank you in advance.

    Hans L
     
  4. MudCrab

    MudCrab Imaging Specialist

    Joined:
    Nov 3, 2006
    Posts:
    6,482
    Location:
    California
    Unless consolidation is used, the original backup image files are not modified by creating additional Incremental or Differential images. This allows you to go "back in time" to the state of your Full backup or any associated Incremental/Differential backups. For example, if you create a Full backup image on Monday and an Incremental Tuesday through Sunday, you could restore your drive/partition back to any of the last seven days.

    If you choose to consolidate your Incremental/Differential backups into your Full backup, then the resulting image will be one that reflects the state of your drive/partition at the time of the latest image included in the consolidation.

    Deleted files/folders aren't really "deleted" from the newly created Incremental/Differential backup, they're just not included because they don't exist at the time of the backup.
     
Thread Status:
Not open for further replies.