Menu

Parchive FAQ (suggestions thread)

2001-11-10
2001-11-19
  • Ryan Gallagher

    Ryan Gallagher - 2001-11-10

    Okay... I'm starting the assembly of a general Parchive-FAQ and later client specific FAQs.

    The purpose of this thread is for the other developers and public to make suggestions of questions (and maybe answers) to be included in the general faq.

    I've grabbed the FAQ from mirror, per wehlus's suggestion as a starting point.

    Please refer to:
    https://sourceforge.net/docman/display_doc.php?docid=7717&group_id=30568

    Reply to this thread with additions, common questions you can think of etc etc.  Any of the project developers are free to physically edit the document in docmanager (although the interface is kinda messy).  Otherwise just make suggestions here.

    Thank you,
    Binerman (the web developer)

     
    • Nobody/Anonymous

      Question; I might not be understanding the way this works (have read the faq), but why can you not reconstruct 1 missing file with 2 par files if you are missing 3 files? 
      The faq just says no you need 3 files (for that situation) is there some reasonably simple explanation for why or is 'no' as simple as it is gonna get?

      Also it says mirror won't repair damaged files, is that basicly where Rarsoft would come in to implement repairs?  Or is it as the faw says mirror is to create missing files and going beyond that is overcomplicating the situation.

      Sorry if these have been answered in the faq already, I was just trying to get more information as this is a very interesting program.

      Keep up the great work!

       
      • blah blahblah

        blah blahblah - 2001-11-16

        >why can you not reconstruct 1 missing file with 2
        >par files if you are missing 3 files?

        Because it uses every other file of a set as well as an additional PAR to rebuild a file. By other file, I mean either the orignal rar or a PAR. So to repair a file, you must have as many files (pars or rars, as long as there is one original non-par) as there were in the original set. So if you've got 2 pars for 3 missing files, you're still 1 file short of having enough data for the PAR algorithm to work on.

        >Also it says mirror won't repair damaged files,
        >is that basicly where Rarsoft would come in to
        >implement repairs?  Or is it as the faw says
        >mirror is to create missing files and going
        >beyond that is overcomplicating the situation.

        Rar has built in functionality to repair files, and does a wonderful job at it. We saw no point in reinventing the wheel, and left it up to rar to handle repairs. Par is for missing data, because rar handles corrupt data already.

         
    • Stefan Wehlus

      Stefan Wehlus - 2001-11-19

      I'm a bit late, but I was busy the last week...

      I think it is better to remove the Mirror-specific questions:
      Why is the program called Mirror? This is no RAID 1...
      So, a W32 version - but I have Linux...
      So this is open source? Where are your sources?

      It is better this way, because the faq is for the global project. And we should replace "mirror" with "par" in the o ther questions.

      Stefan

      P.S.
      If I'll find some time this week, I add a question about the cryptographic point of view.

       

Log in to post a comment.