[Eclug] Debian no longer recognized partitions

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  • Jason Gurtz jason at jasongurtz.com
    Fri Nov 17 13:23:29 EST 2006

     

    On 11/17/2006 11:04, Chacko Cherackal wrote:
    > If this doesn't work I'm going to try Jason's suggestion of forcing 
    > recognition using mknod.  I'm holding off to use that as a last resort 
    > because it seems like something I could use to muck things up even further.  
    
    Terminology is a bit off here...  All mknod does is create files[1]
    there is no "recognizing" or anything like that going on.  UDEV and
    similar are the ones that do auto-recognition.  As you're finding out,
    this type of modern functionality is not very long in the tooth.  This
    manual device creation also used to be handled by a script (even an
    executable in some cases) called MAKEDEV.  I believe that MAKEDEV was a
    redhat invention, eons ago.  One problem (besides extreme pain in
    dealing with dynamic hotpluggable hardware) with manual device node
    creation is that the /dev directory was typically cluttered with
    hundreds of nodes that pointed to hardware that didn't even exist in the
    system.  The worst offender was probably the dozens and dozens of serial
    ports, left from the days of many serial terminals operating off of one
    server.  With dynamic detection and creation, what you see is what you
    have, unless it doesn't work, which leads to your situation.[2]
    
    If you make a mistake using mknod, you won't have screwed anything up,
    and can just delete the files you have created.  I think, but am not
    sure, that you may be able to create these device files not just in
    /dev, but anywhere you want "just in case" (e.g. create /root/dev/sda1
    etc...)  Then it's just a matter of using your software raid tools to
    tie together those device files that you created
    
    ~Jason
    
    -- 
    [1]  OK OK they're device pointers and not *really* files in the sense
    that they contain data.  They are however, just files as far as the
    filesystem is concerned (e.g. you can ls/rm/cat/echo "foo" > to/from
    them just like any other file). NOTE: doing some of those things NOT
    necessarily recommended!
    
    [2] Trivia: Windows has had this dynamic device creation and
    coresponding device nodes for quite some time.  If you dig into the
    kernel API, you can find such things as \Device\Harddisk1 and so on.  If
    you look at OpenVMS (red-headed stepfather to NT), you will see these
    same names...  As is so painfully typical under windows, the user can
    not directly interact with these special files, as one can under Linux.
    
    

     

     

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