RAID6 & WHS Storage in the same system? RRS feed

  • Question

  • Hi All

    I would really like to use the WHS for my "old drives" and keep my RAID5 or in the future RAID6.

    Is this possibly? I would need a drive letter? or at least 2 volumes.

    I would be using a 3Ware 9650 card for the RAID6 (Why..because a full backup of 4TB only cost 1TB of space).

    WHS is build on a 2003 server with this new extendable drive feature.
    So schouldnt it be possible to define a drive letter for the RAID5/6 setup and the rest of the drives on the MB on another?

    Looking forward to hearing from you...
    Friday, November 2, 2007 4:57 PM

All replies

  • Sorry I have seen the post below by Ken Warren...but...

    >>>>>Ken Warren<<<<<

    WHS with a RAID array is an unsupported scenario. Microsoft doesn't test for issues, and help if you have problems could start with "Please break your array and reinstall.". The reasons are probably varied. Drive Extender offers good performance and data protection (of everything except the system partition) in multi-disk WHS systems that have duplication enabled. Some consumer RAID controllers have, umm, "half-baked" drivers. (I've seen arrays that just randomly start re-syncing when there are no hardware issues at all.) Consumer RAID doesn't deliver the performance it promises. RAID arrays are difficult (usually impossible) to expand. Any or all of these could be part of the reason.


    All that said, hardware or motherboard RAID does work. Many testers have had a RAID array in their WHS at one point or another. (I did, for instance.) There have been very few reports of issues that could be isolated to the RAID array. So if you want to try, I don't see any major reason not to, except that it won't be supported.>>>>>>>>

    ...Does this mean that WHS will mix the raid with other Drives you might have connected to the motherboard?

    Sorry for the Dum Q´s but I cant see how you can have no drive letters and still have another drive with the boot installation of WHS?...that would indicate that you could have 2 setups one with HW raid and another for WHS drives?

    Friday, November 2, 2007 5:10 PM
  • Evening,

    You can have a raid array with WHS installed on it, and just possibly, you MIGHT be able to get to your scenario with having the raid array as an added drive letter, but not part of the pool.

    It would mean installing WHS with it's own drives and have that all set up as far as duplication - backups-clients etc., after that, you could add the raid array and just leave it as an extra disk.






    Friday, November 2, 2007 5:18 PM
  • Hi Colin

    That sounds like one way to do it, didnt think that the order of the installation and setup could solve this
    But that would mean that I couldnt use the big storage (RAID TB) for the backups client = store backups?

    So there is no way you can control if a single drive is going to be part of the "WHS drive collection" or not?
    Because if you could mark the RAID array as a single drive then it wouldnt matter if I didnt do everything first and installed the array last?

    Hmmm I guess this might be a stupid idea, I wanted all of the nice monitoring, remote control, webserver control etc....
    And to keep my terrabyte storage on my raid controller.

    (Dont misunderstand me I think its a brilliant idea but if you have many TB and wants nice performace and high availibilty then you need HW raid, and I also wanted to use the RAID array for storage to back up all the other home PC´s in my house hold...)

    Maybee I have to go back to the drawing board...? and rethink this

    My Setup look like this:

    1 Boot drive (Local Sata Disc) so I will not be booting WHS from the array
    3xSATA (Local Sata Disc) for the WHS drive collection.
    RAID Array TB storage 3Ware 9650 controller (8 port so I can expand this when I need to just drop in a extra drive)
    Friday, November 2, 2007 5:34 PM

    I have a similar situation. I love WHS for backups etc., but I was not ready to turn my $400 HBA into a $50 controller to let WHS use the disks. Not to mention moving ~2TB of data while it reconfigures storage.


    I simply installed WHS in VMWare and allocated what drive space I though appropriate to it.

    This is not a supported config, but then neither is RAID.


    Just don't give it more than 2TB in a single volume and you should be fine.



    Friday, November 2, 2007 6:13 PM
  • Hi Timotl

    So what OS are you using win 2003 server ?
    If you extend your RAID setup do you have your raid formattet as dynamic drive to be able to extend it when you ad a new drive?

    Yes I have the same issues a $$$ investment in my homemade NAS storage and no support for RAID in WHS...
    Still thinks its very strange that you cant have "The best of both worlds" must be some hack in the OS that will allow this?

    WHS develophers:  Do you have any solution to our problems?

    Friday, November 2, 2007 6:54 PM
  • I am running Server 2003 Standard on the host box.

    It's been quite a while since I added a drive (ports are full), but I think it was still a basic disk.

    Once the array was finished adding the disk, I think I just used disk manager to extend the partition into the new unpartitioned space. It's been too long for me to be more specific on the steps.




    Friday, November 2, 2007 7:19 PM
  • Casperse, when you install WHS it will format every drive it sees. If you provide RAID drivers at installation, that will include your RAID array.

    So to keep your RAID array, you would have to install WHS, then after installation is complete you could add the RAID drivers. As long as you don't then add the array to your storage pool, you could use it separately from the space WHS manages. But separate means just that; if the array isn't in the pool, WHS won't put anything on it.
    Friday, November 2, 2007 9:41 PM

  • ************************************************
    Erv Walter Wrote:

    Note, you can add a drive (or a set of drives) to the machine without actually adding them to the storage pool.  WHS won't format them until you manually attempt to add them to the storage pool. If you never do that, the drive will just appear as a normal drive on the machine (and won't be managed by WHS).

    Seeker151 wrote:
    First of all I am not having a problem with the program. I think Home server is very good.  But it is a little to easy for more advanced users.  I am using it on a 18 terabyte Aberdeen server. So as you can see the program caps a limit of 2 terabytes. Which I do not like because I have to break up the RAID 6 into smaller volumes which I do not like because it is a hardware raid with battery backup. It is not a big deal but I would prefer if they would make it more like a server. I understand it is based on Server 2003 but it has a limit. The operating system automatically partions the primary drive to use it as a data drive for any space left over. Dont get me wrong I love the program but I wish MS would allow more advanced features for power users. ***********************************************

    First of all I have now found allot of people with excatly the same problem as my self
    Erv See above txt, say that I can just add the Raid array and never add it to the storage pool !!!
    But other report that I could have big problems and the OS could need to be reinstalled.

    Seeker151 say´s that WHS cant tolerate volumes bigger than 2TB is that really true? I thought because WHS is based on a win 2003 the limit now is 256TB in theory....

    If just win 3003 server did have the same functionality as WHS then my problem would be solved

    Friday, November 2, 2007 10:37 PM
  •  Ken Warren wrote:
    Casperse, when you install WHS it will format every drive it sees. If you provide RAID drivers at installation, that will include your RAID array.

    So to keep your RAID array, you would have to install WHS, then after installation is complete you could add the RAID drivers. As long as you don't then add the array to your storage pool, you could use it separately from the space WHS manages. But separate means just that; if the array isn't in the pool, WHS won't put anything on it.

    Thanks sorry didnt understand, its actually a "Feature" when you install the WHS it will "Help" you by adding all the drives it see....

    Just found another problem it seems that WHS dosent use GPT so that means a limit of 2TB so if I wanted to add the drives I would have to have all drives in my RAID as single drives....

    And if I dont add the array to the storage pool, it won't be available to your users according to this post you made Ken:
     Ken Warren wrote:

    However, if you have a RAID HBA, and you're comfortable with installing and configuring drivers and arrays, then yes, you can install it in WHS. There are some caveats. First, there are no tools for managing the array in the WHS Console application. WHS will see it as a single large drive, and will treat it like any other drive in your system. If you don't add it to the storage pool, it won't be available to your users. If you do, WHS will format it and make it available in the pool. If you add your particular array to the pool, you should be aware that WHS uses MFT format for drives. Drives (and arrays) larger than 2 TB require GPT to address the full space available. So when WHS formats it, you will lose 1/2 TB of space. There are ways to convert it back to GPT, but again, it's unsupported. And you run a serious risk of breaking WHS if you try.

    It would seem that I have to use Win 2003 server and not WHS to many unknowns with RAID and WHS space.
    Also not being able to utilize the space on the RAID array makes it a showstopper for me.

    Guess I have to find some tools and software to simulate all the cool WHS features!
    I would like to thank everybody for all your valuable feedback and detailed information!

    Much appriciated have a nice weekend
    Friday, November 2, 2007 10:53 PM
  • Hi just to clarify.... Im new to the WHS scene

    If I just

    1) plug one drive on my Motherboard controller and Install WHS.

    2) Adds my RAID controller and create my 4TB RAID5 setup. 

    3) Add my 3 other SATA motherboard HD drives and copy all the content to the new RAID5 Array

    4) Format the old sata MB drives and add them to the WHS drive (Keeping my RAID5 Array with all my old data)


    Can this be done...I would try this myself but I am still waiting for the DHL and my WHS installation...


    Monday, November 5, 2007 4:12 PM
  • Yes, that should work. You can even share the data on the RAID array, though you can't use the WHS Console tool to manage the shares. That's something that you will have to do yourself.

    If you want WHS to manage drives and shares, it needs to own the drives. In your case, that would mean breaking the array, so you could give the individual drives to WHS.

    The limit you mention in a previous post is on the size of a single disk, BTW. WHS uses MBR-style disks, which are limited to 2 TiB. Someone (elsewhere in the forums) found a way to turn an MBR disk (array, actually) into a GPT disk, which allows for larger "disks", but I don't recall if he had any other issues.
    Monday, November 5, 2007 4:27 PM
  • That dosent sound to bad then

    1) My Array will be larger than 2TB so I would need to format that as GPT...and for that I need a fix?
    I thought that would only be a problem if a 3TB drive existed and you wanted to have it as part of the WHS drives?

    2) Manage my drives...Can I still point to the Array..EX pictures shown on WHS web could be on my RAID array? or does it have to be on one of the WHS drives

    Sorry last Q´s I think I get the picture now ...To bad the WHS SW is delayed...its out of order so will have to wait alittle longer

    Thanks for your clarification much appriciated!
    Wednesday, November 7, 2007 8:30 AM
    1. A RAID array looks, to the operating system, like a single large drive. If it shows 3 TB now, it's already formatted as a GPT disk, and it will continue to be one unless you give it to WHS to manage.
    2. No. WHS knows nothing about any data stored on drives other than those actually in the storage pool. It's an "all or nothing" situation.
    A misconception that you are probably still laboring under is that you will see any performance or safety improvement from a RAID array. You won't. WHS won't (typically) come anywhere near the sustained read performance of a single drive, never mind that of a truly high performance RAID array. And share duplication does a perfectly adequate job of protecting your files. So the only thing you will gain is that you won't have to migrate all your data off the array.
    Wednesday, November 7, 2007 12:04 PM
  • Hi -

    I have the same problem with a RAID 6 array. I absolutely disagree that duplication is as good as RAID. Duplication is just that - double the space for the same stored object. So if you have 1TB of video, pix and stored objects you have to buy 2 TB for duplication and the chances of reading an entire 1 TB drive without an error is only 99.2% so reading all of 2 1TB drives without error is 98.4%. RAID 6 on large drives is absolutely essential for reliability and if one fails the rebuild is done in the background (with slight performance penalty). Duplication also has performance penalties as well. When you are streaming video, delays can be a problem so a caching controller is a plus in that case.

    I would really like to know how to leverage a single large drive in a RAID 6 (on an HP P400 Smart Array controller). Can you split a 3TB logcial it into multiple logical drive at install time? I had trouble doing this so I re-arranged the RAID in a less-than-optimal fashion to get WHS to install.

    Tuesday, August 25, 2009 11:22 AM
  • You can create multiple volumes on your array, and give each of those volumes to Windows Home Server for installation. Each volume will be formatted using the MBR style partition table, and using the NTFS file system. If your RAID HBA supports online capacity expansion, you could even add a drive to an array and tell the HBA to create a new volume of that size (up to 2 TB), then give it to Windows Home Server.

    Should you suffer OS corruption for some reason, though, RAID (any level) will complicate your recovery scenario, becuase of the additional drivers you need. So RAID is still not recommended. And, of course, it's unsupported.

    Your statistics are suspect, though. Depending on who you ask, and what base statistics you believe, drives today have a first year failure rate of around .2 to .4 percent. The unrecoverable error rate is specified per bit, and is usually in the range of 1x1014 to 1x1015 or so, maximum (reality is much lower). Depending on how you want to manipulate those numbers, you could come up with a 10% statistical likelihood of one unrecoverable read error per TB of data read, or .01%, or just about anything in between. :)

    I'm not on the WHS team, I just post a lot. :)
    Tuesday, August 25, 2009 5:47 PM
  • Sorry  it took a while to reply. I have been building out my WHS.

    The statistics are not suspect. They come from IBM based on 40 years of storage experience. :)

    Normally, infant mortality occurs within the first 30 days. First, RAID is always better than discrete disk because it is fault tolerant. Second, software RAID is really not all that good so I would use drive extender before software RAID. Finally, RAID recovery is not a problem if you allocate a spare (which does waste disk as well).

    I have an HP P400 Smart Array Controller with 512MB of cache and the performance is noticable. From boot to even loading up the web browser. I have Wordpress on IIS, 3CX IP telephone system and an email server all stacked on the same box and it is lightnig fast.

    Whereas before I had WHS on a single 1TB drive (Hitachi deskstar - no slouch) and it was sluggish compared to the RAID.

    However, for the normal user, which I am not, drive extender is good enough.

    I should post a presentation I put together on storage futures but it is pretty big. The big hangup with storage is that disk drives have been under the same fundamental constraints for about the last decade. You may want to look at where things are going in the future. SCM (Storage Class Memory) will become pervasive by the end of the next decade and spinning disk will be religated to the role that tape plays today.

    hehe! I work with the guys that  are designing this stuff.

    Sunday, September 6, 2009 10:57 AM
  • Well, as I said, you can install on your RAID array; just create volumes of an appropriate size and let Windows Home Server have them as the "disks" it sees.

    And yes, RAID does still complicate recovery scenarios. You are failing to account for OS corruption or a misbehaved piece of software which renders the server unbootable. Or user error which results in an unbootable server. (I have seen this done: a coworker once opened regedit and deleted HKLM on his workstation. Idiot coworker.) The only recovery for any of these is server reinstallation. Backing up and restoring the system partition is not supported and has a good chance of creating more problems than it solves (disks dropping out of the storage pool, file conflict errors from DE, data loss, etc.) so that's not an answer.

    I would personally be interested in your presentation, but it's probably not appropriate here. Send it to my email address (available in my forums profile; just remove the antispam device.)
    I'm not on the WHS team, I just post a lot. :)
    Sunday, September 6, 2009 2:15 PM