Mirrored Raid as Backup Solution

Discussion in 'Macintosh Computers' started by adamfilip, Oct 22, 2005.

  1. macrumors 6502a

    adamfilip

    Joined:
    Apr 13, 2003
    Location:
    burlington, Ontario canada
    #1
    I have a 200 Gig Internal Hard drive that I use for all my files

    i also have a 200 Gig external Firewire drive that backsup the internal drive

    can i set it up on my G5 so that it is mirror Raided.
    im assuming i can with Disk Utility

    I currently have 150 gigs of stuff on the internal drive
    Problem is if i go an create a raid drive. with the external
    will "Disk utility" erase/format my internal drive to setup the mirrored raid

    can i unplug my firewire drive after and then reconnect when i need it backed up?
     
  2. macrumors G3

    Joined:
    Jul 23, 2002
    Location:
    Sol III - Terra
    #2
    Nope this is not how RAID works.

    RAID 0 is for performance.
    RAID 1 & 5 is some performance gains, and it also keeps a system up and running if a disk fails.
     
  3. macrumors 603

    OutThere

    Joined:
    Dec 19, 2002
    Location:
    NYC
    #3
    Raid 3 (byte level) and 4 (block level) provide a parity disk with a copy of all the data striped across the other disks in the array.

    Raid 3:
    http://www.pcguide.com/ref/hdd/perf/raid/levels/singleLevel3-c.html

    Raid 4:
    http://www.pcguide.com/ref/hdd/perf/raid/levels/singleLevel3-c.html

    Downside: you'll need a hardware RAID system to do it, it can't be done with software RAID.

    Edit: seeing that you have only 2 drives, you can't do RAID 3 or 4, but if you ever have more drives, it's a very safe system.
     
  4. macrumors G5

    CanadaRAM

    Joined:
    Oct 11, 2004
    Location:
    On the Left Coast - Victoria BC Canada
    #4
    Raid != Backup.

    If you do a RAID 1 mirror you may NOT turn off or disconnect your second drive. A Mirror RAID protects you against hard drive mechanical failure, that is all. If you accidentally delete a crititcal file, or munge your OS with a software install, or overwrite a good file with a bad one of the same name, the damage is done immediately to the mirror as well as to the main drive.

    You don't want a RAID. What you really want is a periodic backup, perhaps which you can schedule. Look at Retrospect (commercial), Silverkeeper (shareware) or other programs that can do a backup or a sync between volumes. www.versiontracker.com

    Note: why all of a sudden all the threads confusing RAID with backup??
     
  5. macrumors member

    Joined:
    Oct 14, 2005
    Location:
    Southern California
    #5

    I'm guessing that it's all the marketing that we've seen lately on external SATA boxes. Look at that, then scan quickly over some vague RAID info - mirror!! backup!! I get it, I need a RAID! Only geeks read the details...

    Good news is, this all comes at a time when HD is blossoming and more people may really be in need of a RAID...
     

Share This Page