Mac Pro SAS Card Recommendation

Discussion in 'Mac Pro' started by jollymon6672, Jul 2, 2014.

  1. jollymon6672 macrumors newbie

    Joined:
    Jul 2, 2014
    Location:
    Aldie, VA
    #1
    I have 2 Mac Pro's, 2008/2012, and I am looking to hook up a Omnistor SE3016 16 Hard Drive 3.5" Bay Expander SAS SATA JBOD Rackmount. I need recommendations on that will work for this.
     
  2. DJenkins macrumors 6502

    DJenkins

    Joined:
    Apr 22, 2012
    Location:
    Sydney, Australia
    #2
    Atto gear has always been the go-to fro mac and I've personally used an R348 which was awesome. Their support team is great.

    I'm currently using an Areca card which would be my second recommendation as they are a bit cheaper, quality is good and tech support is almost as good as ATTO.

    You'll need a card with 2 x SFF 8088 connectors. Just make sure you get a proper hardware ROC (raid on chip) card. A non-raid HBA (although tempting at about half the price) won't give you the same reliable configurations as a true raid card.

    I would look at:
    Atto R680
    Areca ARC-1882x
     
  3. jollymon6672 thread starter macrumors newbie

    Joined:
    Jul 2, 2014
    Location:
    Aldie, VA
    #3
    Thanks for the fast reponse...

    I noticed a ATTO H680, do you know the difference? With the dual ports, it states they support up to 8 devices. Does that mean I need two card for a 16 bay unit or does the unit act a one drive?
     
  4. DJenkins macrumors 6502

    DJenkins

    Joined:
    Apr 22, 2012
    Location:
    Sydney, Australia
    #4
    There must be a SAS port multiplier inside, as there is only only one outgoing SAS port on the unit.

    A H680 HBA (Host Bus Adapter) is designed as a passive interface with external RAID arrays that manage the RAID using hardware in the external box.

    As your Omnistor box is a simple JBOD (just a bunch of disks) system, you will need an R680 RAID card to manage the raid for you.

    Both situations work the same, it just depends on which end the RAID is managed at.

    Just to add something else into the mix - a passive HBA (e.g. H680) will technically work with a simple JBOD expansion box (your Omnistor)

    BUT

    You won't get true RAID functionality and your data is essentially unmanaged and vulnerable to failure should any of your disks die. I would not recommend this.

    A true RAID system offers a combination of:
    1. Speed - All disks work together, as opposed to the full load being placed on one disk at a time
    2. Redundancy where one or more drives can fail and your system keeps working while you swap the disk

    What RAID level you choose is up to you. For a 16 bay system, it's typical to use RAID 6 plus 2 hot spares.

    This means up to two drives can simultaneously fail and they will be rebuilt using the hot spares, leaving no interruption to your work at all. However 4 of your disks are used for redundancy, leaving 12 for actual storage.
     
  5. AidenShaw, Jul 2, 2014
    Last edited: Jul 2, 2014

    AidenShaw macrumors P6

    AidenShaw

    Joined:
    Feb 8, 2003
    Location:
    The Peninsula
    #5
    The R680 looks like a good choice. Note that it has http://www.attotech.com/features/CacheAssure/ - technology so that a supercapacitor can save dirty write data in the cache to flash on power failure. You don't want to run RAID 5/6/50/60 without some assurance that your recent writes won't disappear if the power fails. (And you don't want to run RAID 5/6/50/60 without the write-coalescing that write cache gives you.)


    SAS provides a generalized switched fabric that is far more flexible than the limited SATA port multiplier stuff. At SAS prices, all of the cabinets/controllers that I've looked at have the switched fabric.

    The R680 specs say that 256 drives are supported on the 8 SAS ports.

    Also note that the R680 has two connections, each of which has 4 SAS lanes. One connector - 4 lanes. One lane - 32 disks. Four lanes - 128 disks. Eight lanes - 256 disks.

    My HP SAS cabinets/controllers support 256 drives per lane.
     
  6. OS6-OSX macrumors 6502a

    OS6-OSX

    Joined:
    Jun 13, 2004
    Location:
    California
    #6
    Another vote for ATTO!
    Not only is the support team great, the hardware is like WOW! :p
     
  7. jollymon6672 thread starter macrumors newbie

    Joined:
    Jul 2, 2014
    Location:
    Aldie, VA
    #7
    --- Post Merged, Jun 6, 2017 ---
    I know it has been ages since this thread was active, but I came across it again and wanted to express my thanks to all who provided solutions. It worked out great!
     

Share This Page