Handling of NTFS Junction Points by "partition image" backup

Discussion in 'Acronis True Image Product Line' started by reiayanami, Feb 29, 2008.

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  1. reiayanami

    reiayanami Registered Member

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    Does anyone know how Acronis True Image 10 "partition image" jobs handle NTFS Junction Points?

    Specifically, if there was an NTFS junction Point at folder "C:\Data" that pointed to the root of a different partition, would a partition image of drive C: include the data within the different partition that the junction point, pointed to?

    I've tried to find an answer to this question on the general web, within this forum and on the Acronis website but have not managed to get a conclusive answer so any authoritative answers would be most welcome.

    Many thanks in advance.

    Regards,
     
  2. Acronis Support

    Acronis Support Acronis Support Staff

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    Hello reiayanami,

    Thank you for choosing Acronis Disk Backup Software.

    We are sorry for delayed response.

    Please be aware that no current versions of Acronis products support NTFS junction points. We do not recommend backing up partitions where junction points are present. Probably, support for that feature will be implemented in future, however, the exact time-frame isn't available yet.

    Thank you.
    --
    Marat Setdikov
     
  3. K0LO

    K0LO Registered Member

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    Marat:

    Please check with your design team again, because every edition of Windows Vista contains NTFS junction points, and by saying that you "do not recommend backing up partitions where junction points are present" you are effectively saying do not back up any Windows Vista partitions, when your company advertises TI as being capable of doing just that.

    I have backed up and restored my Vista partition with TI 10 several times, and all of the NTFS junction points are restored properly, as you can see from the attachment showing the directory junction for "Documents and Settings" pointing to "Users" (this is viewed on my Vista machine after restoring an image using TI 10).

    Clearly, something is wrong with the advice being given here!
     

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  4. K0LO

    K0LO Registered Member

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    reiayanami:

    I can't answer specifically for the case that you mention (a junction point that is pointing to a different partition) but for the case where the junction point is pointing to a different folder on the same partition, a TI 10 restored image does not duplicate the data in the referenced folder. Rather the image contains only the original folder plus the NTFS directory junction point, as expected.
     
  5. Acronis Support

    Acronis Support Acronis Support Staff

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    Hello k0lo and everyone interested,

    Thank you for choosing Acronis Software.

    I'm sorry for not being accurate enough in my explanation. Let me clarify the point at hand: it's safe to create an image of partition containing junction points that are local to this partition. However, in the case reiayanami described, current versions of Acronis True Image would end up trying to back up the target of junction point as well. But, since it's a different volume that wasn't prepared (locked) for backup, that part might end up containing inconsistent data, if the files are accessed during backup creation. Furthermore, it is likely to create problems after the restoration of such image.

    Summarising the above, it's not recommended to create backups of partitions containg cross-volume junction points with current versions of Acronis True Image.

    Thank you.
    --
    Marat Setdikov
     
  6. K0LO

    K0LO Registered Member

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    Thank you, Marat.
     
  7. shieber

    shieber Registered Member

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    So, does an ATI backup include the data that a junction point points to or does it just include the Junction Point (the pointer)?
     
  8. K0LO

    K0LO Registered Member

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    Yes. :)

    Since a Directory Junction is simply a way of giving two different names to the same folder, then the answer is not either/or but rather "both".

    As an example, Vista ships with a folder "C:\Users" for storing user profiles. Plus, it includes a directory junction called "Documents and Settings" that points to "C:\Users" to maintain compatibility with programs written for Windows XP. So an ATI backup of the whole C: partition will get the "C:\Users" folder and the directory junction "Documents and Settings". But you will not get two copies of the contents of the C:\Users folder (one for the folder and one for the Documents and Settings junction pointer).

    What is suprising about Marat's response above is that if the directory junction points to a different partition then TI will attempt to copy the contents of the folder pointed to by the directory junction. I didn't expect that one (never tried it).
     
  9. reiayanami

    reiayanami Registered Member

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    I also didn't expect this behavior.
    I thought that the ATI only copy the attribute "Junction" and it's "target path" but not the contest of the target.
    If I have a C: partition of 10GB I waited for a 10GB image(not compressed :) ) file not a "10GB + xGB (target GB)"
     
  10. smiley2

    smiley2 Registered Member

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    If you use the OS, then all junction points are supposed to do their job to show contents from other locations.

    But a imaging tool has to save the contents of a partition, and so handle junction points as they are, legal parts of the file system NTFS.

    So one can e.g. roll back a system partition and not loose data intentionally stored elsewhere to keep them.
    This is the way Ghost does it, and only this is a real image 1:1 of a partition.

    my 5 cents :)
     
  11. SHP

    SHP Registered Member

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    Marat:
    I just found this thread. I'm running Vista and recently purchased ATI 11. I also recently moved my "c:/Users" folder to my "d" partition. I have created junctions from "c:/Users" to "d:/users". My "c" partition now contains my OS and program files only.

    Based on your posts, it seems that I will not be able to use ATI to create an image of my "c" partition. Is that correct? If so, I guess I have a few follow up questions.

    First, what options do I have? For example, can I exclude the junctions while doing the image? (I seem to remember reading the ATI 11 allows the user to exclude files from an image.) Obviously it would be much better if the image inlcudes the junctions but not try to image my "d" drive.

    Second, will the clone function still work? Since the clone function locks all of the partitions on a drive, it seems like it should.

    Third, do you have an idea of when Acronis might be taking care of this issue?

    Lastly (this is a question for everyone, I guess), are there any other image programs that will allow me to image my "c" partion with the junctions?

    Thanks.
     
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