How it works? create an image without stop OS

Discussion in 'Acronis True Image Product Line' started by mlumbrer, May 18, 2006.

Thread Status:
Not open for further replies.
  1. mlumbrer

    mlumbrer Registered Member

    Joined:
    Apr 16, 2006
    Posts:
    3
    Hi,
    I have a machine running windows 2000 server. The machine has 2 disk: C and D. By running Acronis installed on disk C: I was able to create a C: image and store the .tib file on disk D. All the process was started from Windows (no boot from a CD)

    My question is: how the image stored is consistent and not corrupted? the Windows OS continues working without any service stopped (FTP and IIS) and the image is done perfectly -it seems.
    What about -if in the middle of the process- there is some OS log writing and registry change, for example?

    Regards
    Mauricio
     
  2. jmk94903

    jmk94903 Registered Member

    Joined:
    Jul 10, 2004
    Posts:
    3,329
    Location:
    San Rafael, CA
    It's done with magic. The programmers graduated from Hogwartz. :)
     
  3. Acronis Support

    Acronis Support Acronis Support Staff

    Joined:
    Apr 28, 2004
    Posts:
    25,885
    Hello Mauricio,

    Thank you for your interest in Acronis Disk Backup Software.

    Here is a description of the unique Acronis Snapshot technology:

    Once Acronis True Image initializes the backup process of a volume (which logically corresponds to a single partition, if there are no Dynamic Disks), Acronis Snapshot Manager flushes the file system mounted to that volume temporarily freezing all the operations on the system volume. Immediately thereafter, the Snapshot Manager driver creates a point-in-time view of the system volume and a bitmap describing the used sectors on this volume. Once the bitmap is created, the filter driver unfreezes the I/O operations on the system volume. It generally takes only several seconds to create a point-in-time view of the volume. After that, the operating system continues working as the imaging process is under way.

    Acronis True Image reads the sectors on the system volume according to the created bitmap. Once a sector is read, the appropriate bit in the bitmap is reset. In its turn, the Acronis driver continues working to hold the point-in-time view of the system volume. Whenever the driver sees a writing operation directed at the system volume, it checks whether these sectors are already backed-up, if they are not, the driver saves the data to the sectors that will be overwritten to a special buffer created by the software, then it allows the sectors to be overwritten. Acronis True Image backs up the sectors from the special buffer, so that all the sectors of the point-in-time view of the system volume will be backed up intact. Meanwhile, the operating system continues working and the user will not notice anything unusual in the operating system functionality.

    If we are talking about complex applications such as databases please read the following FAQ article:
    http://www.acronis.com/enterprise/products/ATIESWin/faq/backup-exchange-server/

    Thank you.
    --
    Anton Sherkhonov
     
    Last edited: Dec 1, 2006
  4. Peter2150

    Peter2150 Global Moderator

    Joined:
    Sep 20, 2003
    Posts:
    17,039
    See JMK was right. It is magic.:D
     
  5. aoz

    aoz Registered Member

    Joined:
    Jun 8, 2005
    Posts:
    223
    Acronis,
    that was one of teh best answers I've ever seen; and, seems to make a lot of sense in operation, also.

    NOW, what happens in a "file and folder" backup? Is a similar method used?

    thanks
    Nick
     
  6. Howard Kaikow

    Howard Kaikow Registered Member

    Joined:
    Apr 10, 2005
    Posts:
    2,802
    ALL backup programs do no more than backup the content of sectors (or files) at a point in time.

    Does not matter whether it is the boot drive or the system drive or some other drive on which the sectors/files live.

    Most systems have files that are changed often. For example, my scanner came with software that recreates a .ini file once per minute, whether or not I am actually using the scanner.

    With TI, you can boot with the recovery disk and backup from the virtual OS created by TI.
     
Thread Status:
Not open for further replies.