OEM: supported way for C: on HD0 and D: on HD1 RRS feed

  • Question

  • Hey folks,


    Is there a supported way for me as an OEM system builder to place C: and D: on separate drives, vs. being forced to have C: be a 20gb partition on the first drive and D: being the rest?

    I haven't seen a way to do this inherently, but I'm pretty sure I can make it work with a bit of magic.


    If I've overlooked something, please let me know.


    Ryan Rogers

    Thursday, January 24, 2008 10:02 PM


  • No, there is no supported way to do this.

    I'll be interested to hear if you come up with a way to do it, though.
    Friday, January 25, 2008 3:14 AM

All replies

  • No, there is no supported way to do this.

    I'll be interested to hear if you come up with a way to do it, though.
    Friday, January 25, 2008 3:14 AM
  • Ken, you've got mail.


    Once I get this working (or give up trying), I'll share with the community.


    I'm fairly confident though I can make this work.


    However, getting it to work and have MS support me as a System Builder who deploys installations like this remains to be seen.




    Friday, January 25, 2008 9:10 AM
  • Oh, another quick question.

    If I do get this working, any thoughts on what WHS will do if HD1 (D:\) fails?  ;-)


    Normally, this is a use case the software doesn't need to handle, as MS avoids this unpleasantry by forcing D: onto the system physical disk, making a complete system rebuild or restore necessary in order to get back up and running.  Ugh!


    I'm wondering if the restoration process that gets D: tombstones back after an OS reinstall would also come into play here and handle this case as well.  I would think it would, but I may need to format, partition, and drive-assign the new D: drive first before rebooting back into WHS.




    Friday, January 25, 2008 9:49 AM
  • Ryan, someone else recently tried the experiment of pulling his system drive, formatting D:, and putting it back. He had hosed his storage up too badly to be able to continue, and he was willing to risk his data to find out the results. I believe he said that WHS rebuilt all the control structures. That would make sense; loss of the D: partition is part of what happens when you replace the system drive, or when you sysprep your WHS for duplication, and the system needs a way to recover.

    But as I've said elsewhere, the system drive is the least important drive in your system. It's the one least likely to contain unique real data; the only time Drive Extender will store unduplicated files, or components of the backup database, etc. on C: is when it's forced to do so by lack of space elsewhere. Everything else is metadata that can be replaced or recreated easily (though rebuilding the tombstones can take a very long time, if you've got a lot of data).
    Friday, January 25, 2008 1:12 PM
  • Yeah I wouldn't expect that to work at all!  With D:\ completely empty, WHS has no choice but to recreate the control stuctures from scratch, which would ignore all of the data on the secondary drives.


    But if they were already in place since they had been imaged from the original D:\ partition after install... ;-)


    Yep, the time to rebuild the tombstones is a big concern.  Another concern is the data loss that will happen if I'm only backing up HD0 as discussed in the other thread.


    I think I could address the latter with a utility to handle this.  A fairly simple scanner program could find differences between the shadow threes nad the primary tree after rebuild, and fill in the missing tombstones.  Not directly, but through re-copying the file through the public share. 


    That would leave just the first issue, which I plan on testing first hand with some real customer data and see how it performs before I make a final decision one way or the other.





    Friday, January 25, 2008 4:00 PM
  • I can understand what your doing, but why? It's not going to make data safety any more robust and I cannot imagine Microsoft accepting it for a recognised system builder.




    Friday, January 25, 2008 5:53 PM
  • Actually that's not quite true if you look at it from all aspects.  Statistically speaking, there is more data safety and it is more robust.  In particular, what if the rebuild takes days as Ken suggests, and then you lose another drive during that window?

    If the rebulid takes minutes, or is not necessary at all, then you have just made your data more secure, as you no longer have a long, protracted window during which you have a single point of failure to data-loss.


    Of course, you also have to consider that your server was available during that time, vs. down for hours or days.  For whole house controllers that have a service expectation of 24/7/365, that is important.  WHS is the most appropriate operating system that MS makes for this type of appliance based on price point and features.

    For users who have 5 to 10 or more TB of data, a soup-to-nuts backup is not realistic.  However, all secondary data drives are redundant if you have duplication turned on across the board.  It's only the primary data drive that is not backed up.  Ken has confirmed that WHS will not elegantly handle backing up and restoring just this single drive that has no redundancy.


    Splitting the two drives allows the operating system to be backed up, restored, and managed independently.  This flexibility also results in data safety.


    If the system partition becomes corrupt or needs reinstalling, I can apply a previous saved image of that drive to it's replacement, and be back up and running in under an hour.  I can be back up in minutes if I had the foresight to have an imaged drive standying by ready to hot-swap in.  Either way, the D: primary data doesn't change one bit, and when the server comes back up it's going with no rebuild time necessary.  No window of time at which you are a drive failure away from losing data.


    In the "normal" case, if C: and D: are combined and I lose the system drive, I will *LOSE CHANGES* applied to any files since D: was backed up, as Ken as confirmed.  You are supposed to restore everything, or nothing.  If I don't restore and instead reinstall fresh, then I don't lose the changes, BUT during tombstone rebuild I'm open to single drive failure syndrome.  Either way, you are absolutely open to loss that you wouldn't be if you could have  managed the system partition as it's own drive.  There is more data safety.  It is more robust.  Not by a huge margin, but it is.  And if that second drive fails, that margin will make all the difference in the world.


    I do not plan on oem'ing a system with just C and D split. If I do offer C and D split, it would be a RAID 1+1 configuration, and it will be a full-tower or 4U configuration.  The key is mirroring the primary data partition is where you get the big ROI.    So whether C/D are combined on HD0 and that is mirrored, or C/D are separated and both are mirrored, the mirroring is the key to the big boost in data security, robustness, AND availability.


    - Ryan

    Friday, January 25, 2008 7:08 PM
  • Ryan,

    Did you ever have any success with this?  I am trying very hard to achieve exactly that... physical disk separation between the system partition (C:) and the primary data partition (D:).

    I just bought WHS a week ago (the SKU that has PP1 included), and I've been wrestling with it a bit to try to get it the way -I- want it.

    I have tried a number of "tricks" to make it work, such as using offline 3rd party disk tools to copy the data partition to the second physical disk, delete the original data partition, and resizing the system partition to the entire physical disk.

    Didn't work, of course.  WHS booted up fine, but it wrought all kinds of havoc, declaring the system disk to have an error... but the repair option was greyed out.

    Yes, I'm an IT professional, and I've been in the industry for a long time now (~15 years).  Yes, I realize I am not the "target audience" of WHS and I could very easily build a Win2K3 or Win2K8 server instead.  However, I really want to make WHS work, because there's just some things that are totally cool about it that the traditional corporate Windows versions don't have.

    Being able to separate these two is the only hurdle left until I achieve the "happiness" I wanted from WHS.  "Officially supported" or not, if I can get it working, I'll be happy!

    I'd love to hear of any success stories!

    EDIT: Never mind... I managed to figure it out.  It involved careful and painstaking registry edits (in addition to the partition replications / resizing with an offline disk utility), but I now have exactly what I wanted, and it works. :)  I wish it was a simple process that I could document, but the reality is, if you aren't REALLY comfortable mucking around in the registry (especially when it has do with disk and volume IDs), you don't want to do it, especially if there's any critical data on the server.  I was more confident since I have a clean install here, no data to lose!  I'm sure though that the ability to relocate the primary data partion could indeed be added to WHS (in an official capacity) if Microsoft chose to do so.

    • Edited by EdgeDC Friday, November 7, 2008 10:46 AM
    Friday, November 7, 2008 6:55 AM
  • Edge, it's certainly do-able. It's probably easier to do if you interrupt setup at an appropriate point (I can't tell you what that point is, I'm afraid, as I haven't actually tried this) and separate the partitions.

    But before you start relying on your server, consider that you're now running in an extremely unsupported state. At a minimum, you should test a server reinstallation to see what happens. You may need a server reinstallation, even if you use RAID 1 for your system drive, because there are things that can cause an OS to become corrupted and unbootable (a failed software install, a bad storage driver, etc.). RAID won't protect against that.

    And I don't know that you'll be able to install future updates to Windows Home Server, either. It's possible that future updates will make changes which presume the drives and partitions are laid out the way WHS normally does. I'm not saying this will happen, but nothing you did is a documented or supported configuration change for WHS, so Microsoft is unlikely to take anything you did into account.

    I'm not on the WHS team, I just post a lot. :)
    Friday, November 7, 2008 5:19 PM
  • Ken,

    Thanks for your feedback.  I now have a "dumb question" to ask... how exactly do I start a reinstallation?  Booting to the DVD again only gives me the "New Installation" option again.  Do I really have to create my own restore DVD in some fashion? It seems pretty bad to me that the OEM DVD does not search the drive(s) to see if a previous WHS install was there, in case someone just wants to reinstall the OS and keep the data.

    Interesting that you brought up RAID - I never mentioned RAID in my previous post... because I know how much of a hot button that is, having read other threads. :)  RAID is not the concern here.  I just want my C: drive to completely fill up one drive, and run my primary data partition (D:) on a separate drive.  RAID need not be part of the discussion!

    One of the other "tricks" I tried is interrupting the install during one of the reboots to resize the C: partition to the entire drive, in the hopes that the rest of the install would find the other drive and use it instead for the D:.  It looked like it was going to work, until it came up to the "Creating Primary Data Partition" step, at which point it bombed out and showed me the q_setup.log file (which contained, amongst other things, errors that it couldn't find qs.ini).

    Again, I recognize that this is not a "supported" configuration, but I fail to understand why Microsoft didn't give some kind of "advanced" method to achieve this, even if it required supplying an option in an INI file or something.  Just as disappointing as the bootable DVD not having a "reinstall" option right then and there.
    Sunday, November 9, 2008 6:14 PM
  • In the initial graphical portion of setup, are you supplying drivers for all your storage devices at the hardware detection screen, so that all your drives are visible to setup? If you are, and you're not getting an option for reinstallation, I think you have your answer: You will be unable to complete a server reinstallation in the event of OS corruption or other problems.

    As for why Microsoft doesn't give an advanced option for this, look at the target audience. Enthusiasts are important, because we're early adopters and will push the product in directions that Microsoft never through of, but if WHS is to succeed, it has to sell to people with far less technical expertise. The primary target market isn't going to install WHS on their own hardware, they're going to buy an HP MediaSmart Server or equivalent from another vendor. The only people who will be installing WHS are enthusiasts, OEMs and system builders, all of whom can be presumed to be technically knowledgeable. But WHS will be sold in (effectively) a single configuration, as far as the OS and partitions are concerned. This reduces support and development costs significantly.

    As for RAID, it's the logical next step. :) And no, it's not supported.

    I'm not on the WHS team, I just post a lot. :)
    Monday, November 10, 2008 4:03 AM
  • I have recently gotten a copy WHS and right out of the box the install was flawless for me.. As for me this day one for WHS and so far absloutly love it.
    As i have been testing and tring out all the different functions of WHS, and one thought came into my head. how can i split the C and D to differnt drives? i was thinking of haveing a SSD as the primary C: drive and then have a 1TB or raid setup of all the data. it would really be nice if there was an out-of-the-box way to do something like this. but i guess i am forced to split the drive a differnt way. but as this is not a "supported" way, anyone willing to give me a few hints as to what to watch out for?
    Monday, November 10, 2008 4:54 AM
  • See the post above my last post, where EdgeDC says that he doesn't get a server reinstallation option after splitting the drives. This is not a situation you want to find yourself in; if you experience OS corruption due to e.g. a failed software install, you will be unable to recover without starting over from scratch.
    I'm not on the WHS team, I just post a lot. :)
    Monday, November 10, 2008 1:12 PM