Migrating Data Unto a RAID 10

Discussion in 'Mac Pro' started by NoManIsland, Feb 22, 2010.

  1. NoManIsland macrumors regular

    Feb 17, 2010
    I currently have two 1 TB Seagates in my Mac Pro (2.8 Ghz 2008), with one being my main drive and the other my Time Machine drive. I am wanting to add two more 1 TB drives of the same model and set up a software RAID 10 across all four drives. Problem is, I need to migrate almost 1 TB of data off the current setup onto the new, but I can't afford an external, especially just for this task. Does anyone know of a way to accomplish this? I initially had the idea of restoring from TM unto the new RAID 1 set, then erasing the two original drives and reconfiguring them into a RAID 1 set, but then I realized I'd have to erase all four disks to stripe the two pairs - is there any way around this?
  2. NoManIsland thread starter macrumors regular

    Feb 17, 2010
    Another Idea

    What if I were to stripe the new set of two drives, move the data on to that set, then stripe the old two drives and setup that set as a mirror (so RAID 0+1 as opposed to RAID 10)? Would that allow me to transfer the data without an external drive? Or do I have to erase both sets of drives to reconfigure them as a mirror? (reminder that this is using Disk Utility) I could definitely use some help with this as I have to buy the drives soon. :eek:
  3. JesterJJZ macrumors 68020


    Jul 21, 2004
    Buy an external, do your transfer and return it if you have to. Or borrow one from a friend. Trying to get around it won't work. You should have a backup anyway, even if you use a protected raid. Get a 2TB external and use it for TM.
  4. nanofrog macrumors G4

    May 6, 2008
    JesterJJZ is right.

    You're going to have to have access to a separate drive to serve as a backup location. There's no way around this, as the initialization process will wipe any drives included in the arrays (10 = pair of mirrors are created, then those are striped together, hence 1 + 0, which is written as 10 for convenience).

    As you're going to be limited for internal space, it might be best to go external with it. If you need more than 2TB (single drive), then go with an eSATA and a Port Multiplier enclosure.

    I'll also presume with this question, you're planning on skipping a proper RAID card (as discussed in other threads)?
  5. NoManIsland thread starter macrumors regular

    Feb 17, 2010
    Thanks guys for the info. I had a feeling that there wasn't a way around it, I was just hoping for a trick that could limit the costs as I am in the slow season of my business and will be doing this upgrade on imaginary money :( I do eventually plan on getting a big external for Time Machine and offsite backup, I just hoped it wouldn't have to be right away.

    Nanofrog, yes I am planning on using the software RAID in OSX as it will represent a cost savings and I don't think that the overhead will be a problem for me (also I don't use Windows). If you have a recommendation for an inexpensive card, I may reconsider and just live with limited space for a while longer.
  6. antmo macrumors member

    Feb 20, 2008
    You could grab another 1TB fast drive and a 2TB green drive and then just do RAID 0 on the three fast drives and use the 2TB for TM... it would probably not cost you much more money than 2 1TB fast drives and you wouldn't need another external. Then later, if you needed more internal space, just get another 1TB for the RAID 0 and stick the 2TB into a cheap external enclosure... just throwing out suggestions.
  7. NoManIsland thread starter macrumors regular

    Feb 17, 2010
    Hello antmo, and thanks for the suggestion. I've considered something along those lines, but in your configuration I would end up with 3 TB usable space and only 2 TB for Time Machine, would I not? The third drive would essentially go to waste as I couldn't back up anything I put on it.

    My default plan was just to get a 2 TB internal and use it for Time Machine, freeing up one of the 1 TB and doubling my free space - I just was hoping to do something elegant (1 volume) that would allow me to both have mirrors and eventually Time Machine as well for double redundancy.
  8. antmo macrumors member

    Feb 20, 2008
    True, you'd only be able to back-up 2 of 3 TB, but I'm assuming you're not going to completely fill all 3TB for a little while at least... so until you start using over 2TB of the RAID for non-system/non-backed-up data, the 2TB should suffice... but yeah, if you think you're going to use more than 2TB right away, that config is a bad idea.

    Essentially, the idea would be to use the 2TB until you outgrow that for backup, then you could get another 2TB green drive and another 1TB internal drive and make a 4TB JBOD external backup and add the other 1TB into your internal RAID 0 for a 4TB RAID0, then you're golden with big and size-matched working and backup arrays...

    again, just suggesting what I'd do in that situation :)
  9. nanofrog macrumors G4

    May 6, 2008
    What exactly do you need as far as:
    • Port count, and if it needs to be internal/external
    • System model (i.e. '09's would require an adapter if you want to use the HDD bays, which will add $165USD to the cost; if it's an '08 or earlier, then you may need an extension cable to get the iPass cable <aka MiniSAS = SFF-8087> to the RAID card, which is $90USD). Both adapters are from the same place, and they're the only supplier.
    • RAID levels desired for the card (not just what you want to start with, but possibly use in the near future)
    • Boot capability (i.e do you want OS X to be booted from an array/drive on the card)
    • Throughput requirements (limited with 4x drives, but it can give me an idea of what you need, especially with future expansion)

    In general, I'll say go with a model made by Areca. ARC-1212, ARC-1210 (uses SATA ports), or in a pinch, the Highpoint RR4310. All three are EFI bootable (OS X) and can also boot in a BIOS environment (but can only have one or the other, as no card can contain both). They're also 4 port cards.

    If you need more ports, I can help you there as well. But I do need details, as there's more than just port counts in the differences. Processor speeds and cache capacities (some can even allow you to expand it via a DIMM socket) for example.


    A stripe set allows you to retain all the available capacity, but you don't have any redundancy. Either way, no matter what you do, you must run a proper backup (and I do give you credit for getting a drive up for TM). :)

    And as antmo indicated, if you don't need speed, Green Power drives are a good way to gain additional capacity for the lowest cost. This makes them excellent drives for backup. They can be used as primaries as well, but as they're slower, have limits (some can be gotten around by using more of them, but not always; again, it depends on the specifics).

    I'm a tad lost here, as I don't know what you have, or are trying to achieve exactly. So if you could give some specifics (system in hand, including drives,... and what you're doing with it), it would help immensely. ;)
  10. NoManIsland thread starter macrumors regular

    Feb 17, 2010
    Hello Nanofrog - sorry for the confusing posts :(

    I have a 2.8 Ghz 2008 Mac Pro that currently has two 1 TB Seagates, one being my main drive, the other being my Time Machine drive. I've run out of room, so I need capacity, but I also need my new storage to be reasonably fast because of my usage.

    I'm a classical composer and I bought my Mac Pro to run the Vienna Symphonic Library, a 270 GB (and growing) behemoth sample library, which I use in Logic to realize the instrumental parts of my compositions in progress, or as a final rendition for those pieces which don't get performed live. As such, I need a lot of storage (as the VSL isn't my only sample set), but I need to be able to stream the samples rapidly to avoid stuttering.

    I also have a very large classical music collection I keep in AIFF format on my computer and I've very much run out of room for that as well. So basically I have a couple reasons to need capacity and one to need speed. Because I had once lost a few years of compositions to an unfortunately timed HDD failure, I also am very concerned about a rigorous backup or redundancy set up.

    I don't have a lot of money right now to devote to upgrades, but I'm willing to save and make do until I can do something proper with the data on my system, and I liked the idea of RAID 10 + external TM drive as a safe arrangement with good speed - but that is limited in capacity. I had also considered making an upcoming upgrade an SSD RAID 0 in the lower ODD bay as a way to boost Logic's performance, but that does nothing to solve the capacity or safety situations.

    Let me know your thoughts. :eek:
  11. nanofrog macrumors G4

    May 6, 2008
    OK. :cool: The '08's are easier to deal with when it comes to RAID, especially if it's via a 3rd party card using the HDD bays.

    Ideally, it sounds as if you could really benefit from SSD for an OS/application drive (or even an array), and use RAID for storage. But given your capacity needs for the libraries and limited budget, it's not yet feasible.

    So the least expensive route is to go with a stripe set (RAID 0), and make absolutely certain you've a backup system in place (schedule backups in the software, as it's easy to forget to do them manually).

    I still don't know what your budget or throughput requirements are, but given a single SSD is capable of ~220 - 250MB/s reads, I'll use that as a target.

    So a 3x drive stripe set would be able to do this (sustained, not random access, which is what Logic would really benefit from, but it's still better than a single drive). That leaves you a single HDD bay for a backup drive, say a 2TB WD Green Power.

    Hopefully, we'll get you dialed in as best as possible for your budget. Just keep in mind, random access though improves with a stripe set, is still no where near what an SSD can do.

    You might be able to get the OS and Logic on a single SSD, and use a stripe set to hold both working data and the libraries. You need to think about this, and let me know if it's a possiblility.

    Remember, a stripe set can produce n*single drive throughput = array throughput (i.e. 100MB/s for a single mechanical drive * 3x disks = 300MB/s).
  12. NoManIsland thread starter macrumors regular

    Feb 17, 2010
    Thanks Nanofrog. Okay, so I'm thinking about this as a possible setup:

    1 x 80 GB Intel X25-M SSD or 2 x 40 GB Intel X25-V SSD in a software RAID 0 for OS + Apps (right now my system and apps take up about 50 GB, but I can trim that)

    2 x 1 TB Seagate 7200.11 HDDs (the drives I already have) in software RAID 0 for sample libraries and data storage

    1 x 2 TB Samsung F3EG for Time Machine

    The total costs for this per Newegg Canada would be $524.28 after taxes and shipping for the Samsung and the two 40 GB SSDs, versus $570.20 for the Samsung and the single 80 GB SSD. Correct me if I'm wrong, but I would anticipate the former being the better path for my setup?

    I'm thinking that if I get the set of two 40 GB SSDs, I'd drop them in the spare ODD using the two extra SATA ports, whereas, if I chose the single SSD, I'd mount it in the final bay probably.
  13. nanofrog macrumors G4

    May 6, 2008
    Either approach will work (I've not seen a review on the X25-V (40GB) yet, so I've no idea how good/bad they are compared to the X25-M).

    Theoretically, yes, the former (2x 40GB drives) would be a better way to go, but as I mentioned, I haven't spotted a reveiw yet (only seen product announcements so far, but it's been a bit since I looked; curious about real throughputs, TRIM,...). If you find something on them, please post a link. ;)

    Either way (single or array), I'd put the SSD/s in the ODD bay. The ODD_SATA ports will work for OS X, but not Windows (just to let you know).
  14. NoManIsland thread starter macrumors regular

    Feb 17, 2010
    I found only this review:


    It seems as if the X25-V is comparable in most ways except for write speeds. I imagine that is probably less important on an OS/App drive then it would be on a data drive, so do you think I'd be better off getting the pair and striping them, or, since the cost is similar, getting the 80 GB instead? With the 80 GB, I could get another 80 GB down the road and stripe them to have speed + capacity as apps get fatter.

    As for putting the array in the ODD bay, I agree, and I don't use Windows except through Fusion, so I don't think that will be a problem.
  15. nanofrog macrumors G4

    May 6, 2008
    Thanks. I was hoping for more, but that's OK (TRIM results,...).

    The write speeds do suck, but if they're used primarily for reads, it won't be much of an issue (2x in a stripe set would be ~90MB/s or so, which isn't awful; comparable to a decent mechanical drive).

    If you're willing to live with the 80GB and add one in later, then that might not be a bad idea.

    As per Windows, once you set up a RAID array, you won't be able to boot Windows properly (not possible via BC - ever, nor as a separate drive as it does something in the firmware that prevents the single drive from functioning properly). So this would almost certainly affect the VM method as well.

    You can get around it, by using a SATA controller, and I've located a really cheap one (here). Attach a drive to that, and it gets the drive off of the ICH (Southbridge), where the system's SATA settings won't affect the drive. So there is an easy, and inexpensive solution to the problem (card is only 2 ports, but you can configure them as you wish; 2 + 0, 0 + 2, or 1 + 1 internal/external respectively).
  16. NoManIsland thread starter macrumors regular

    Feb 17, 2010
    Thanks for the link. I actually just found an interesting solution that raises some new questions. Trans International has a mounting solution called the DX4:


    There's an option to bundle it with a Rocket RAID 2310. If I got a DX4 and mounted the single 80 GB SSD or dual 40 GB SSDs on it, I'd have room to expand the array in the future and I could leave the ODD bay as a spot for a Blue-Ray drive or two 3.5" drives as per MaxUpgrade's MaxConnect:


    or Trans International's Pro Caddy 2:


    This would give me a lot of flexibility, and mounting the SSD in the DX4 would make it easier to add a proper RAID card in the future (but it would have to be a four port card).

    So you're saying that if I use one of the extra SATA ports for a single SSD, I wouldn't be able to run Fusion properly, or is that only for the striped pair?
  17. NoManIsland thread starter macrumors regular

    Feb 17, 2010
    Has anyone here had experience with Trans International's DX4?
  18. nanofrog macrumors G4

    May 6, 2008
    It's definitely interesting, and there's other possibilities as well (allows you to stuff 4x 3.5" drives in both optical bays; 2x per). Bit pricey though.

    Don't touch it. It's a FakeRAID controller, and I've had problems with such devices in the past.

    You can still get more ports than that, and mount elsewhere, such as the optical bays or externally. Once the drives have a home (physically), it's just a matter of cabling (including power).

    Only if it's striped (or any other array setup under Disk Utility).
  19. NoManIsland thread starter macrumors regular

    Feb 17, 2010
    Okay, I think my plan is as follows:

    1) Purchase a Samsung F3EG to use as the new Time Machine drive in HDD bay 3, then backup to it.
    2) Software stripe the two 1 TB drives already in HDD bays 1 and 2, then restore the data to them.
    3) Run off this set up until I can afford both the 80 GB SSD and the DX4. Once they are purchased, move the OS and Apps onto the single SSD, mounted in the DX4 and connected to one of the spare SATA ports.
    4) Once funds and lowering prices allow, get three more 80 GB SSDs and mount them in the DX4, all hooked up to a 4 port RAID card (not the 2310 :p).
    5) Add more storage to the fourth bay, possibly to the ODD bay later on.

    Does this seem like a reasonable game plan? Also, will it allow me to use Fusion successfully at each stage? I'm looking for maximum flexibility and longevity here, as I usually keep my towers for 10 years or so :eek:.
  20. nanofrog macrumors G4

    May 6, 2008
    No, this won't work. Fusion has a problem with OS X's software RAID. The OS needs to remain on a single drive (SSD or HDD). If you have this and an array via OS X (Disk Utility), then the Windows drive needs to be on a SATA card.

    Disk Utility seems to modifiy the system's firmware, which prevents Windows from loading. This happens even when you try to natively boot into Windows.

    You can try it if you wish, but I'd be surprised if you can get it to work (unless there's been an update to Fusion that allows it to work). Otherwise, the issue described not only makes logical sense. Part of it is also that I recall someone posting on this (OS X software RAID = Fail with VM of Windows).

    For it to work, the OS must be on a single drive or an array run off a proper RAID card (keeps Disk Utility from making a change to the SATA controller settings in the firmware).
  21. NoManIsland thread starter macrumors regular

    Feb 17, 2010
    Hmm... could I wait until I had the SSD running as a singleton, and stripe the 1 TBs then? Would this obviate the problem because Fusion is on the single drive, or would it still fail as I'd have to keep the VM files on the striped drives? I don't think I could keep the VM files on the SSD, because each one has a minimum disk allocation of 40 GB. Also, would Crossover fail as well? My Windows usage is minor enough I could squeak by using only Crossover if it would still work (I'd prefer not to however).
  22. nanofrog macrumors G4

    May 6, 2008
    It would still cause a failure, as the array is controlled by OS X (Disk Utility). Apparently, it's making a change in the firmware, and affects the ability to load Windows.

    Single drive operation is fine (and it means for every drive attached to the logic board).

    It wouldn't really matter. Capacity would be an issue if it worked, but I seriously doubt it will.

    The best thing to do, is contact the maker of Fusion, and ask about running it with OS X's RAID functions under Disk Utility. Hopefully, they may have found a work-around.

    I think it would be fine, but I've never used this software (appears to be emulation, as there's no need for a Windows license or installation).

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