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RAID 5 Vs JBOD RRS feed

  • Question

  • Hello All

     

    I had a Highpoint Rocketraid 454 card with 4 x 120GB hard drives setup as Raid5 - pre-WHS.  While WHS would have probably installed fine on this, consensus seemed to suggest that it would be better for WHS to control redundancy, duplication, etc.  I tried to set it up as 4 individual disks, but the BIOS for the RAID card seemed to insist that even as JBOD, each array should consist of two drives.

     

    So my final setup has WHS seeing my primary 200GB hard drive and 2 x 240GB arrays from the Highpoint card.  I guess this means that if 1 of the 120GB drives fails, it will take out a 240GB partition/array that WHS sees.

     

    Others seem to have been able to get each disk recognized by WHS individually.

     

    Any pointers, or should I just not worry?

     

    ash720

    Saturday, May 5, 2007 7:21 PM

Answers

  • Hi

    I have the exact same card from Highpoint. I have 6 * 260GB HD attached and I do not have them setup as a raid or jbod arrays.

    When you boot up and go into the setup for the rocketraid, you will see all the hard drives, just don't create any arrays. WHS will see the new hardware and you have to install the server 2003 drivers from the Highpoint web site for WHS. You can then add the individual drives to WHS. Works like a charm...


    Saturday, May 12, 2007 5:25 PM

All replies

  • JBOD (SPAN) obviously requires a minimum of 2 drives. IMHO a very risky way to store your data. To get  the individual disks to show up  you'll probably have to delete all arrays in the Highpoint BIOS
    Saturday, May 5, 2007 10:29 PM
    Moderator
  •  brubber wrote:
    JBOD (SPAN) obviously requires a minimum of 2 drives. IMHO a very risky way to store your data. To get  the individual disks to show up  you'll probably have to delete all arrays in the Highpoint BIOS

     

    Actually JBOD is Just a Bunch of Drives.  There is no raid/span/etc.  Brubber: I think you are talking about RAID-0 for "spanning" disks.  JBOD is just "plug and go, you'll have 4 seperate HDDs show up in My Computer".

     

    Tuesday, May 8, 2007 4:06 AM
  •  Eric A. Duncan wrote:

     brubber wrote:
    JBOD (SPAN) obviously requires a minimum of 2 drives. IMHO a very risky way to store your data. To get  the individual disks to show up  you'll probably have to delete all arrays in the Highpoint BIOS

     

    Actually JBOD is Just a Bunch of Drives.  There is no raid/span/etc.  Brubber: I think you are talking about RAID-0 for "spanning" disks.  JBOD is just "plug and go, you'll have 4 seperate HDDs show up in My Computer".

     

     

    Not correct IMHO.

     

    JBOD is concatenating multiple (different sized HD's) into one virtual disk where all the sizes add up. If this is done by the controller only one (virtual) HD is presented to the OS. I agree this is not an official RAID level. Linux users sometimes have a different interpretation of JBOD

     

    RAID0, striping can also be done using multiple HD's of different size, however there the total size you end up with is the size of the smallest disk multiplied by the number of disks

     

    For a good description of RAID levels go to http://en.wikipedia.org/wiki/Standard_RAID_levels

    Wednesday, May 9, 2007 5:39 AM
    Moderator
  • JBOD is another example os spanning....

     

    From what you described as your setup, this arrangement is not good, since not even WHS may manage your storage to your advantage.

     

    I would suggest breaking it up and adding the drives singly under WHS....

     

    Can you configure it under Windows to be single drives?

     

     

    Wednesday, May 9, 2007 6:01 AM
  •  

    My understanding of the way WHS dealt with drives was that it would be better to attach each drive individually.  However, the BIOS of the Highpoint card seems to only allow me to create a RAID array (or two) of several different flavours or setup the drives as JBOD.  If I choose JBOD I cannot select each individually, but must combine at least two to form a JBOD array.

     

    I cannot work out how to persuade the card to see each drive individually.  It seems from suggestions above that this is a bit risky ie if one drive fails, it will take out the two drive array.  I was hoping to use the card as a simple 4 channel IDE controller.  Maybe I would be better to ditch the card and just buy a simple 4 channel IDE controller.

     

    Ash720

    Wednesday, May 9, 2007 2:19 PM
  • Can't you just break up the existing array, connect each disk to an individual channel en set one disk as boot disk?
    Thursday, May 10, 2007 12:19 AM
    Moderator
  • I'll stick with RAID5.

     

    Duping files across disks is a waste of space IMHO. When this goes RTM I'll rebuild on a jumbo RAID5 set and be done with it.

     

     

     

    Saturday, May 12, 2007 4:19 AM
  • Hi

    I have the exact same card from Highpoint. I have 6 * 260GB HD attached and I do not have them setup as a raid or jbod arrays.

    When you boot up and go into the setup for the rocketraid, you will see all the hard drives, just don't create any arrays. WHS will see the new hardware and you have to install the server 2003 drivers from the Highpoint web site for WHS. You can then add the individual drives to WHS. Works like a charm...


    Saturday, May 12, 2007 5:25 PM
  • Vince

     

    Excellent.  OK, I'll give that a go.

     

    Thanks

     

    ash720

    Monday, May 21, 2007 8:08 PM
  • Well, my Adaptec 4 port SATA drive claims that it is in JBOD mode, and makes each of the drives I have connected to it available to the OS, with no spanning, mirroring etc.

     

    Looking up on Wikipedia, it explains that JBOD is concatenation, but "Some RAID controllers use JBOD to refer to configuring drives without RAID features. Each drive shows up separately in the OS. This JBOD is not the same as concatenation." which is what my Adaptec SATA RAID card is doing.

    Sunday, May 27, 2007 10:54 AM