differential/incremental alternating

Discussion in 'Acronis True Image Product Line' started by elliottq, May 30, 2007.

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  1. elliottq

    elliottq Registered Member

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    Please clarify for me. If I make a full data backup, can I then alternate differential and incremental backups relative to that? For example could I use this strategy to save time of doing full diff backups.
    Full data backup
    incremental for 5 day
    diff re full day
    incremental for 5 days
    etc.
    after 1 month do a new full backup
     
  2. Tabvla

    Tabvla Registered Member

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    Hello Elliottq, welcome to the Forum... :D

    The short answer is "Yes", you can create either Differential or Incremental or both with reference to the original Full backup.

    In practice you may find it a little more difficult to manage and it would probably be advisable to keep a written (pen & paper) Backup Record in a notebook to ensure that you don't confuse the different types of backup. Using the "Notes" section of the ATI backup process may also be helpful.

    Please note that I have underlined "with reference to" above. It is important that your backups (whatever the type) are in reference to the original Full backup and not to each other.

    The following example may provide some clarity:

    Sun : Full backup
    Mon to Fri : Incremental backups (By Friday you will have a 6-file archive)
    Sat : Differential with respect to the previous Sunday's Full backup (2-file archive)
    Sun : No backup (let us assume that you don't use the computer on a Sunday)
    Mon to Fri : Incremental backups (By Friday you will have an 11-file archive)
    Sat : Differential with respect to the first Sunday's Full backup (still a 2-file archive)
    Sun : No backup
    Mon to Fri : Incremental backups (By Friday you will have an 16-file archive)
    Sat : Differential with respect to the first Sunday's Full backup (still a 2-file archive)

    ..... and so on....

    If the above is not clear please get back to the Forum.

    :)
     
  3. Acronis Support

    Acronis Support Acronis Support Staff

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    Hello elliottq,

    Thank you for choosing Acronis Disk Backup Software.

    Please note that both differential and incremental backup archives depend on the initial full backup.

    Incremental backups are also depend on the previous incremental backups. Therefore, to restore the date from the incremental backup you will need ALL the previous incremental backups and the initial full backup.

    Differential backup archives are independent from each other and each differential backup contains all changes against the initial full archive. To restore the data from a differential backup you should have this differential backup and the initial full backup only.

    This Knowledge Base article <Difference between Incremental and Differential Image> could also be useful.

    Thank you.
    --
    Aleksandr Isakov
     
  4. Menorcaman

    Menorcaman Retired Moderator

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    Hello Aleksandr,

    Does this mean TI 10.0 fixes the previous "feature" whereby you require the initial full backup and ALL the associated differentials in order to carry out a successful backup archive validation?

    Regards
     
  5. snmavronis

    snmavronis Registered Member

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    Oh, thanks for explaining that. Thats a good way to explain how it works.

    Also, I'm wondering about the "last" Friday full backup as used in my schedule. At first I thought the last choice would equate to a 5th Friday if it occured. But on a 4 Friday month, it also does the "last Friday" at the same time causing a failure on one of them. Here is my backup schedule senario. Maybe there is a better way to do it?

    Monthly Full Disk Image Backup (F:\Friday1Backup.tib) “first” Friday

    Friday2 Full Disk Image Backup (F:\Friday2Backup.tib) “second” Friday

    Friday3 Full Disk Image Backup (F:\Friday3Backup.tib) “third” Friday

    Friday4 Full Disk Image Backup (F:\Friday4Backup.tib) “fourth” Friday

    Friday5 Full Disk Image Backup (F:\Friday5Backup.tib) “last” Friday (if there is a 5th Friday in the Month)

    Node# Daily Differential Disk Image Backup (F:\Friday1Backup#.tib)
    - Each Differential does a cumulative backup of changes since the last Monthly (F:\Friday1Backup.tib) full image backup on Saturday, Sunday, Monday, Tuesday, Wednesday, and Thursday. It creates a new cumulative Image Backup file (but just the changes since last full Monthly backup) on each day (except Fridays) of the Month.
     
  6. Tabvla

    Tabvla Registered Member

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    The use of the word "only" in this context may be misleading.

    There is absolutely no reason why you should have "only" the initial Full backup and a Differential backup. For example....

    Let us assume that you create a Differential backup every day for a week. Therefore at the end of the week you will have 8 files - the original Full backup and the 7 daily Differentials.

    Let us further assume that at some time after the end of the week you realise that a program that you installed in the middle of the week is creating problems. You could is this situation select a Differential prior to the installation of the troublesome program and restore your system to that point in time.

    T.
     
  7. Acronis Support

    Acronis Support Acronis Support Staff

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    Hello Menorcaman,

    We are sorry for the delayed response.

    Currently Acronis True Image 10.0 Home handles differential validation the same way as before, as described in this post.

    Thank you.
    --
    Marat Setdikov
     
  8. Acronis Support

    Acronis Support Acronis Support Staff

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    Hello snmavronis,

    Thank you for choosing Acronis Disk Backup Software.

    We are sorry for the delayed response.

    Please notice that "last [day of week] of month" choice is literally the last: fifth if there are five, fourth if there are four.

    Please notice that your desired schedule could be easily set using Acronis Backup Location with 1 month storage period limit and a backup task to create a new full backup after every 6 differential ones. Please see chapter 8 "Scheduling tasks" of the respective User's Guide for detailed instructions.

    Thank you.
    --
    Marat Setdikov
     
  9. Menorcaman

    Menorcaman Retired Moderator

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    Hello Marat,

    As I suspected - the validation bug has not been fixed. Therefore, given that users should always validate an image after its creation and prior to a restore (unless they carry out an immediate test restore to a spare drive), they will need to retain all copies of differential images associated with a particular full backup.

    Regards

    Menorcaman
     
  10. snmavronis

    snmavronis Registered Member

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    Thanks,

    Are you speaking of Acronis Backup Locations as described under the Acronis Backup Server section 3.5 in the TrueImageEnterpriseServer9.1_ug.en.pdf documentation?

    I probably installed it wrong or incomplete being the first time I used the software? I only installed TI Enterprise Server with Universal Restore on our Windows 2003 Server box. I didn't elect to install the Management Console or the Acronis Backup Server because I didn't understand why I needed it or if my license for TI Enterprise Server with Universal Restore included those peices too. I was probably just going for a simple to use, quick and dirty approach!

    Do you recommend they be re-installed from scratch and in what order?
     
  11. Acronis Support

    Acronis Support Acronis Support Staff

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    Hello snmavronis,

    I am sorry, for some reason I was under impression you are using Acronis True Image 10.0 Home.

    However, you are correct that Acronis Backup Server (in Acronis True Image 9.1 Enterprise Server) provides essentially the same functionality as Acronis Backup Locations (in Acronis True image 10.0 Home). You can install Acronis Backup Server on the same computer you're backing up and set it to manage your backups. You can find the detailed instructions on how to install and use Acronis Backup Server and other components of Acronis True Image 9.1 Enterprise Server in the respective User's Guide.

    Thank you.
    --
    Marat Setdikov
     
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