Drive recognition

Discussion in 'Mac Pro' started by macmesser, Mar 6, 2013.

  1. macmesser macrumors 6502a

    Joined:
    Aug 13, 2012
    Location:
    Long Island, NY USA
    #1
    How are drives identified to the system? Is there some unique identifier that the drive sends to the system on boot up or when it is mounted? Can a drive be moved from an external enclosure on an eSATA card to an internal bay and still be recognized as the same drive? I want to move my Time Machine drive from enclosure to an internal bay and I'm wondering if TM will still recognize the drive as a backup drive. Thanks for any insights.
     
  2. Tesselator macrumors 601

    Tesselator

    Joined:
    Jan 9, 2008
    Location:
    Japan
    #2
    • Thee's some buss protocol and FileSystem behavior that adds various amounts of identity and structure information as needed.
    • Yes, several levels of it. But the entire dance isn't very complex - Surprisingly simple actually.
    • Yes. And that's a VERY broad "yes". For example you could stripe a 3-drive RAID volume connected internally and then place just one of the three on a USB 2.0 or 3.0 interface and the striped volume will still operate perfectly - maybe slower because of the USB interface speed, but it'll still function the same.
    • Yup, sure will. If it's needed just point TM to that volume after moving and it'll pick up right where it left off.
    • Sure, no problem...
     
  3. macmesser thread starter macrumors 6502a

    Joined:
    Aug 13, 2012
    Location:
    Long Island, NY USA
    #3
    That's good news. Makes things simple. Thanks!

    Makes sense. Sort of like this I guess: Disk device has partition map. Partition has a volume property. Volume would be completely logical structure, also unique and global to Mac system. Disk tells Mac about partitions, Mac gets volume property of each partition and mounts (possibly multi partition) volumes. But I don't see why there's a need to re-point TM to the moved disk if its TM volume is global to the Mac system. Apps must have a lower level of consciousness than the OS. :) Will look into this on a rainy day when I have time to peruse docs.
     
  4. Tesselator macrumors 601

    Tesselator

    Joined:
    Jan 9, 2008
    Location:
    Japan
    #4
    It shouldn't need to. I'm said that just in case. :)
     

Share This Page