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WHS primary drive disaster prevention RRS feed

  • Question

  • Hi folks, quick question.

    One of the things confusing me, and frankly worrisome as well, is the feeling that if you lose your WHS primary drive you could risk losing all data on the server.  I assume this is not the case and I am not understanding a few things, so, some specific questions.

    1.  Any reason why I could not use hardware raid 0 or 5 specifically for the WHS primary drive (for obvious reasons, to protect against drive failure).

    2.  Any reason why I could not use a backup tool like Acronis True Image to backup/clone the Boot and Data partitions?  By data partition I am referring to the partition that contains the pointer files NOT the shares with data itself.   The goal here, obviously, is to have a copy of the server OS partition and the data partition ready in case of an emergency.   Since I plan on shadowing all my shares having a primary drive backup should be all I need to assure I am convered from anything other than destruction of the whole system.

    3.  Can the OS and Data partitions on the primary drive be cloned?


    Basically it seems that WHS provides good tools to protect your share data and your client pcs via backups, but provides nothing to help prepare against possible primary drive failure of the WHS itself.  And no, backing up ALL of the WHS server data itself for this is not a solution for me atm, that is why I am shadowing all shares in the first place ;)

    Thanks
    Thursday, March 19, 2009 5:38 AM

Answers

  • 1. It's not supported, you may have problems installing, and also if for some reason you need to do a server reinstall this may cause problems.

    2 / 3. You can clone the OS and DATA partition on the primary drive, however you will almost certainly have major problems after restoring them.

    In case of primary drive failure the only supported way to recover is doing a server reinstall. In most cases this will preserve you data and client backups, unless part of the actual data is also stored on the primary drive. You will however need to repeat all post install modifications you made such as creating users, install add-in's or other third party software, connect clients and so. 

    Please also read the Technical brief Drive Extender for some more background info on WHS storage.
    Thursday, March 19, 2009 8:38 AM
    Moderator
    1. You would not want to use RAID 0, which is striping and less reliable than a single drive. Using other forms of RAID is unsupported, but not (usually) hard to get working. You are on your own if you have problems with the array, though.
    2. (and 3) The information that you would want to back up is too volatile. Any backup, using any tool, will typically be out of date within minutes.
    As Brubber has said, the only supported option in the case of a system drive failure is server reinstallation. The amount of pain that represents to you is directly proportional to the amount of "unsupported" customization you have applied to your server.

    I'm not on the WHS team, I just post a lot. :)
    Thursday, March 19, 2009 11:59 AM
    Moderator

All replies

  • 1. It's not supported, you may have problems installing, and also if for some reason you need to do a server reinstall this may cause problems.

    2 / 3. You can clone the OS and DATA partition on the primary drive, however you will almost certainly have major problems after restoring them.

    In case of primary drive failure the only supported way to recover is doing a server reinstall. In most cases this will preserve you data and client backups, unless part of the actual data is also stored on the primary drive. You will however need to repeat all post install modifications you made such as creating users, install add-in's or other third party software, connect clients and so. 

    Please also read the Technical brief Drive Extender for some more background info on WHS storage.
    Thursday, March 19, 2009 8:38 AM
    Moderator
    1. You would not want to use RAID 0, which is striping and less reliable than a single drive. Using other forms of RAID is unsupported, but not (usually) hard to get working. You are on your own if you have problems with the array, though.
    2. (and 3) The information that you would want to back up is too volatile. Any backup, using any tool, will typically be out of date within minutes.
    As Brubber has said, the only supported option in the case of a system drive failure is server reinstallation. The amount of pain that represents to you is directly proportional to the amount of "unsupported" customization you have applied to your server.

    I'm not on the WHS team, I just post a lot. :)
    Thursday, March 19, 2009 11:59 AM
    Moderator
  • Ken Warren said:

    1. You would not want to use RAID 0, which is striping and less reliable than a single drive. Using other forms of RAID is unsupported, but not (usually) hard to get working. You are on your own if you have problems with the array, though.
    2. (and 3) The information that you would want to back up is too volatile. Any backup, using any tool, will typically be out of date within minutes.
    As Brubber has said, the only supported option in the case of a system drive failure is server reinstallation. The amount of pain that represents to you is directly proportional to the amount of "unsupported" customization you have applied to your server.

    I'm not on the WHS team, I just post a lot. :)


    Yeah I meant raid 1 :)

    Brubber: Brubber why would you say that I may have problems with a hardware raid array on install or reinstall?  Is this a known issue or an assumption?  I find it strange that a WHS would uniquely have problems installing on a hardware raid array where other versions of Windows would not.   If this is a known issue and there is something specific about WHS that makes it unique in this regard can you explain why?  

    I understand why you wouldn't need to use raid for the drives holding shared folder data, but not why you wouldn't want to use it for the primary drive.  Seems like it would be a pretty prudent thing to do to me.

    You also say that the only "supported" way to recover is to do a server reinstall which in "most" cases will preserve your data and client backups.  Most doesn't sound like 100% of the data and makes it sound like this method is prone to some amount of data loss.  That's not good enough.   If WHS creates pointers on the primary drive that point to the actual data files and you cannot back this up OR protect it using a raid array then it seems that it's very risky using WHS unless you double your storage.   It also makes the WHS file duplication worthless as a data protection mechanism as it was intended.

    Also note that the use of a RAID array is to avoid reinstallation since your array itself is the recovery mechanism in the case of a drive failure. 
    Thursday, March 19, 2009 2:39 PM
  • A server reinstallation will preserve all the data in your shares in the following situations:
    1. You are performing the reinstallation because of OS partition corruption, not because of drive failure.
    2. You are performing the reinstallation because of drive failure, but you have duplication turned on for all shares.
    3. You are performing the reinstallation because of drive failure, you don't have duplication turned on for all shares, but your server has never stored any files on the D: partition (only tombstones).
    1. and 2. are easy to determine. 3. is a catchall, and the end user probably can't determine this easily "before the fact". This is why I generally recommend to my friends to simply turn on duplication for all shares.

    Backups and data placed in the storage pool by server add-ins are a separate question. Backups aren't duplicated, so if any components of the backup database are stored on the D: partition, they will be lost if the system drive fails. This normally means the loss of the entire backup database. Add-in data uses a mechanism built into Windows Home Server called "application folders"; these participate in Drive Extender just like other folders, and they can have duplicaiton turned on. If it's turned on, you're protected against the loss of any single drive, just as in the first case above. If it's not (and I think at least most add-ins that use application folders don't turn it on) then your data will fall into case 2. or 3.

    I'm not on the WHS team, I just post a lot. :)
    Thursday, March 19, 2009 3:14 PM
    Moderator
  • Ken Warren said:

    A server reinstallation will preserve all the data in your shares in the following situations:

    1. You are performing the reinstallation because of OS partition corruption, not because of drive failure.
    2. You are performing the reinstallation because of drive failure, but you have duplication turned on for all shares.
    3. You are performing the reinstallation because of drive failure, you don't have duplication turned on for all shares, but your server has never stored any files on the D: partition (only tombstones).
    1. and 2. are easy to determine. 3. is a catchall, and the end user probably can't determine this easily "before the fact". This is why I generally recommend to my friends to simply turn on duplication for all shares.

    Backups and data placed in the storage pool by server add-ins are a separate question. Backups aren't duplicated, so if any components of the backup database are stored on the D: partition, they will be lost if the system drive fails. This normally means the loss of the entire backup database. Add-in data uses a mechanism built into Windows Home Server called "application folders"; these participate in Drive Extender just like other folders, and they can have duplicaiton turned on. If it's turned on, you're protected against the loss of any single drive, just as in the first case above. If it's not (and I think at least most add-ins that use application folders don't turn it on) then your data will fall into case 2. or 3.

    I'm not on the WHS team, I just post a lot. :)

    Thanks Ken, that clarifies for me that a loss of tombstones does NOT mean permanent loss of access to the data on the shared folder storage (on other drives).  Correct?   Reinstallation/new installation will see that data and use it?

    In any case I'm still very interested in a response to Brubber's comment about why RAID for the primary drive (hardware raid, 1 or 5) "could cause problems" and is unsupported.  That seems very much counter to the way Windows 2003 servers are deployed in the field today and I can't understand how WHS would be any different.  If experts make a comment that using hardware raid can cause problems then we have to assume that is a real case and would like to know why.

    Thanks much

    Thursday, March 19, 2009 9:49 PM
  • That's correct; there is a tombstone check/rebuild process that will run as one of the last stages of a server reinstallation if needed. Warning: it takes a very long time to run. :)

    RAID is unsupported for a few reasons. Most are laid out in this WHS team blog post. In addition, a reasonably reliable RAID controller will add significantly to the cost of an OEM server, so much so that in all probability a consumer would decline to make a purchase. Finally, consumer-grade RAID often doesn't perform well, and the drivers may be less than fully baked.

    I'm not on the WHS team, I just post a lot. :)
    Thursday, March 19, 2009 11:59 PM
    Moderator
  • Ken Warren said:

    That's correct; there is a tombstone check/rebuild process that will run as one of the last stages of a server reinstallation if needed. Warning: it takes a very long time to run. :)

    RAID is unsupported for a few reasons. Most are laid out in this WHS team blog post. In addition, a reasonably reliable RAID controller will add significantly to the cost of an OEM server, so much so that in all probability a consumer would decline to make a purchase. Finally, consumer-grade RAID often doesn't perform well, and the drivers may be less than fully baked.


    I'm not on the WHS team, I just post a lot. :)



    Some additions to Ken's comments:

    1. WHS is a consumer grade product. Good quality REAL hardware RAID controllers could double the price of a system. For enterprise environment (W2K3 based servers) cost is important, however reliability, performance and availability are often more important.
    2. Personally I think a true hardware RAID controller would do little harm in WHS and could potentially be advantegeous in case of single drive failure. However most "consumer" hardware RAID solutions (including the popular on board controllers) are in fact still host based and require software (drivers) to run. The robustness of the RAID array is therefore dependant on the qualitiy and availability of the drivers. Deployment of these RAID solutions is not always straightforward.
    3. WHS uses specially designed technology for file storage. This results in some issues / features which make WHS different from W2K3 and ultimately made me decide not to use RAID in my own WHS systems, for example:
      1. Have a look at the size of the D partition in windows Explorer in a WHS system with a few 1TB data disks. It will tell you the amount of free space + the amount of used space is larger then the capacity of the disk (could even be the amount of used space is larger then the capacity of the disk. 
      2. Shadow copy function (VSS, previous versions) is affected in such a way that previous appear to be there but are no longer accessible.
    Back to your original question, IMHO RAID is not a backup solution, it's mainly there to ensure high availability in enterprise environments and makes little sense for data protection in most cases. Also as Ken detailed WHS has a solution in place to recover from primary drive failure. If you have the disk space available there's also a simple method to enable duplication of the backup database which will make it recoverable even when it's (partially) stored on the D partition.
    Friday, March 20, 2009 4:16 AM
    Moderator
  • Thanks for the response.

    It sounds to me, opinions on cost and "intent" aside, a hardware raid array, probably raid 1, is a good way to insure against the need to perform the, imo, troublesome recovery process WHS requires.  I would MUCH rather invest in two small SATA drives and a decent raid controller to RAID 1 the system and data partitions than I would in having to reinstall the OS and hope that everything comes out alright in the end.

    Friday, March 20, 2009 6:17 AM
  • Btw, thanks for the blog reference Ken.  However I have to point out that that post is more of a marketing post on the benefits of WHS drive extender technology than anything else ;)   I think that there is a glaring weakness in WHS which is specifically what this post is about, the robustness of recovery for a primary drive failure in a WHS server.   For that RAID is perfect imo, but yes, probably cost prohibative when looking at a total cost of the box perspective.

    However I think that a WHS is still much an enthusiast type of product and given the option you'd be suprised what some folks are willing to pay to get something that is dependable.  And I know the OEM business very well, I'm directly involved in it, and these kinds of things can be put together in a fashion that doesn't add hugely to the cost of the base system.  More certainly but not several hundred dollars more.
    Friday, March 20, 2009 6:22 AM
  • SkeetersSpot said:

    Btw, thanks for the blog reference Ken.  However I have to point out that that post is more of a marketing post on the benefits of WHS drive extender technology than anything else ;)   I think that there is a glaring weakness in WHS which is specifically what this post is about, the robustness of recovery for a primary drive failure in a WHS server.   For that RAID is perfect imo, but yes, probably cost prohibative when looking at a total cost of the box perspective.

    However I think that a WHS is still much an enthusiast type of product and given the option you'd be suprised what some folks are willing to pay to get something that is dependable.  And I know the OEM business very well, I'm directly involved in it, and these kinds of things can be put together in a fashion that doesn't add hugely to the cost of the base system.  More certainly but not several hundred dollars more.

    Of course it's a marketing piece. But did you read it carefully, and perchance follow the very first link in that blog post? You will find much real meat there.

    RAID costs: the general rule of thumb in this market is that adding $1.00 to the Bill of Materials (BOM) cost of a product will raise the retail price of that product by at least $4.00. If I can buy a good (i.e. hardware XOR, solid drivers, long history of reliability/performance) RAID controller for $100, HP could probably work a deal to get it for $50 (or maybe a bit less). That still adds $200 to the cost of the MediaSmart Server. Probably plus a redesigned case, to allow 5 drives instead of 4 (making it possible to get the MSS to 2 TB internally was probably pretty important). You would be lucky to buy the MSS for less than $750 when all is said and done, and HP would be intentionally cutting their profit to the bone just to meet a price point. So yes, hundreds more. And at that price, it wouldn't sell.

    BTW, I know of no RAID controllers that will do all that Windows Home Server would require that cost as little as $100. At a minimum, WHS would require RAID level migration (assuming it shipped with two drives in RAID 1 and needed to switch to RAID 5 on the addition of a third drive) and online array/volume expansion. And it would need to do this on the fly, with no intervention from the end user. A more realistic cost for such a controller would be $200-$250, and at that price you're looking at a $1,000 MSS.


    I'm not on the WHS team, I just post a lot. :)
    Friday, March 20, 2009 11:39 AM
    Moderator
  • I've read both posts and frankly I see the same thing, lots of slamming of RAID in order to promote WHS media extender technology.

    Also, it seems that you may be missing the point of this entire exercise.  Since WHS drive extender tech provides absolutely nothing in the way of protection for the sys or data partitions, it's a completely irrelevant point in this conversation.  This is a dialog about protecting the primary drive data only, not the user data in shares that are duplicated.  I've already stated that I have no need for RAID there as I would wholeheartedly agree that the way WHS duplicates data on different drives is a very good solution, for user data protection and availability.

    But it doesn't get you out of trouble if your primary drive fails and you CAN end up losing data if the reinstallation/rebuild process fails.  And on top of that WHS provides NO backup method for the primary or system partitions.  Frankly this is a horrible oversight.   I'm suprised it seems this point can't be agreed upon instead we keep getting derailed into discussions of WHS drive extender technology which isn't applicable to the discussion.

    So if it's not RAID then give me and everyone a solid solution for protecting the systems primary drive data from drive failure or corruption.  So far I don't see one other than RAID or extremely frequent cloning :D

    And I don't mean to be confrontational here.  I think WHS is a fantastic product or I wouldn't be asking.  But I get frustrated when I see what appears to be an intentional effort to avoid the real problem and no solution provided.
    Friday, March 20, 2009 7:52 PM
  • SkeetersSpot said:

    I've read both posts and frankly I see the same thing, lots of slamming of RAID in order to promote WHS media extender technology.

    Also, it seems that you may be missing the point of this entire exercise.  Since WHS drive extender tech provides absolutely nothing in the way of protection for the sys or data partitions, it's a completely irrelevant point in this conversation.  This is a dialog about protecting the primary drive data only, not the user data in shares that are duplicated.  I've already stated that I have no need for RAID there as I would wholeheartedly agree that the way WHS duplicates data on different drives is a very good solution, for user data protection and availability.

    But it doesn't get you out of trouble if your primary drive fails and you CAN end up losing data if the reinstallation/rebuild process fails.  And on top of that WHS provides NO backup method for the primary or system partitions.  Frankly this is a horrible oversight.   I'm suprised it seems this point can't be agreed upon instead we keep getting derailed into discussions of WHS drive extender technology which isn't applicable to the discussion.

    So if it's not RAID then give me and everyone a solid solution for protecting the systems primary drive data from drive failure or corruption.  So far I don't see one other than RAID or extremely frequent cloning :D

    And I don't mean to be confrontational here.  I think WHS is a fantastic product or I wouldn't be asking.  But I get frustrated when I see what appears to be an intentional effort to avoid the real problem and no solution provided.


    Personally I think you're right a decent RAID solution would be the best way to protect the primary drive, however I do think this beyond most ordinary consumers needs (and budget). Even if server reinstall fails any data on the the secondary drives will be preserved. IMHO only weak point is situations where non duplicated data get stored on the primary drive. Server reinstall is in most cases hassle free, although sometimes time consuming, especially on systems with large amounts of data.

    Recovering from a single failing disk in a decent RAID 1 array is usually no problem, at least if you have a proper spare at hand. What many people forget however is the possibility of failing RAID adapter. Recovering from such a failure often turns out to be a major challenge even for data recovery experts, especially if you can not get your hands on an identical controller with the same firmware. (With WHS concept you will however still have server reinstall option)

    Therefore IMHO a RAID 1 solution would require a decent hardware controller, preferably with a hot spare in place and an identical controller + another disk stored in a safe place, at least if you want to be reasonably sure you don't ever need  to do server reinstall in case of disk or controller failure.

    I also agree current solution can be improved. I would opt for a solution which performs regular automated backup of  C partition to an external disk / tape drive / cloud backup /or even WHS data or spare disk, combined with an option rebuild tombstones after restore of such a backup.
    Friday, March 20, 2009 9:15 PM
    Moderator

  • Personally I think you're right a decent RAID solution would be the best way to protect the primary drive, however I do think this beyond most ordinary consumers needs (and budget). Even if server reinstall fails any data on the the secondary drives will be preserved. IMHO only weak point is situations where non duplicated data get stored on the primary drive. Server reinstall is in most cases hassle free, although sometimes time consuming, especially on systems with large amounts of data.

    Recovering from a single failing disk in a decent RAID 1 array is usually no problem, at least if you have a proper spare at hand. What many people forget however is the possibility of failing RAID adapter. Recovering from such a failure often turns out to be a major challenge even for data recovery experts, especially if you can not get your hands on an identical controller with the same firmware. (With WHS concept you will however still have server reinstall option)

    Therefore IMHO a RAID 1 solution would require a decent hardware controller, preferably with a hot spare in place and an identical controller + another disk stored in a safe place, at least if you want to be reasonably sure you don't ever need  to do server reinstall in case of disk or controller failure.

    I also agree current solution can be improved. I would opt for a solution which performs regular automated backup of  C partition to an external disk / tape drive / cloud backup /or even WHS data or spare disk, combined with an option rebuild tombstones after restore of such a backup.

    That Brubber is the kind of response I was hoping for and makes perfect sense.   In reality no solution is perfect.

    In any case I'm now running RAID 1 on my primary drive and WHS replication on all data on my data drives.

    My concern about recovery and data being preserved has been comments I've seen that seem to imply that reinstalling WHS on a system, where the existing data pool drives are not ordered the same, can be problematic.  Is it true that WHS may not see the data properly in this case?   Say you change motherboards, or your sata controller(s), such that the drive orders change, is there metadata on the drives that tell WHS about all of the relationships of those drives for recovery?   Ultimately that's the big concern.  Imo, WHS should be designed that if you lose the primary drive and even recreate the entire system (but retain the data drives) you should be able to do a full recovery/reinstall with zero risk of data loss since the data is retained.  If this is not true isn't it no better than raid?

    Thanks
    Sunday, April 12, 2009 3:16 PM
  • That Brubber is the kind of response I was hoping for and makes perfect sense.   In reality no solution is perfect.

    In any case I'm now running RAID 1 on my primary drive and WHS replication on all data on my data drives.

    My concern about recovery and data being preserved has been comments I've seen that seem to imply that reinstalling WHS on a system, where the existing data pool drives are not ordered the same, can be problematic.  Is it true that WHS may not see the data properly in this case?

    No.  The problem is with the primary drive, not the secondary drives.  You can have the secondary drives in any order and it should still reinstall.  However, if the primary drive is not plugged into the first port on the motherboard, you may not get Server Reinstallation as an option.  However, if that occurs, all you have to do is change the order so that the primary drive is in the correct port.

    Say you change motherboards, or your sata controller(s), such that the drive orders change, is there metadata on the drives that tell WHS about all of the relationships of those drives for recovery?

    There is a reg file.

    Ultimately that's the big concern.  Imo, WHS should be designed that if you lose the primary drive and even recreate the entire system (but retain the data drives) you should be able to do a full recovery/reinstall with zero risk of data loss since the data is retained.

    That's how it is. :)  (And even if you can't get Server Reinstallation as an option, you don't lose the data.  Each drive is configured using NTFS and can be read by any computer that knows that file system.)

    If this is not true isn't it no better than raid?

    Thanks

    Sunday, April 12, 2009 4:29 PM
    Moderator
  • I came here to the forums looking for 'worse-case scenarios' and how they're handled.  The "general" information directly ON the WHS consumer site is just that, very consumer oriented.

    After being a RAID 1 user, and big believer in how it's saved my ____ many times, I'm come to a few conclusions at WHS and DE services.  I thought I'd share those thoughts and my conclusions:

    - WHS doesn't seem to be built to use ON a Main User PC, but as an external storage/backup media server... and it does this purpose very well.  In fact, I love the idea of putting my videos, photos, music and programs (full installs, original files) on this type of Home Server.

    - You have to consider complete destruction of ANY RAID or WHS when it comes to redundant backup systems.  By complete I mean, what if your house burns down.  What if that side of the house floods, what if lightening strikes, dog chews on it, it bursts... etc.  Be prepared to lose your personal photos and documents which are irriplacbable in most cases.  Watch the news... when you see people fleeing houses, what do they take.  Photos and Family.  You can't replace either.

    - All 3 of my home computers run WinXP SP3 and have RAID1 drives.  As well, I have an external RAID1 backup drive for images of those home PC's.  In addition, I use one of my smaller external drives for storage in a media-safe, fireproof safe (can you tell I'm a digital photographer?).  On top of that, when I put new digital photos on MY main PC, not only do I back them up to my external drives, but it's easy to push a few backup buttons and I back up to my wife's PC as well as my RAID1 backup drive.  The fireproof drive comes out about once a month for backups of 'critical' and personal data, or just after a big vacation or event with thousands of photos.

    - I like the idea that I can "mirror" (copy) data that I choose on a WHS box.  Remember, I have a RAID1 on my PC, but I still backup to an external drive.  If I was to do a full backup of my PC to a WHS box, I don't have to mirror the data therefore saving a TON of space.  Why bother with a copy on a WHS?  If it's lost there, I still have my original computer running... right?  It's just a backup.  If it's lost, so what.  I would however, "copy" (have to get used to that word instead of "mirror") all my media on the WHS of course.

    So...  I feel that WHS sounds perfect for my need to keep access to all my media available to all my devices, while ensuring that my data is safe (outside of a fire/etc).  With this type of system, I can possibly stop having to copy a backup to my wife's computer, as well as to mine.  I can serve them to multiple devices in a separate box.  However, I'll still keep my RAID1 drives on my PC's.  

    WHS sounds like a great backup device as well as an even better media server.


    Sunday, April 12, 2009 6:09 PM
  • That Brubber is the kind of response I was hoping for and makes perfect sense.   In reality no solution is perfect.

    In any case I'm now running RAID 1 on my primary drive and WHS replication on all data on my data drives.

    My concern about recovery and data being preserved has been comments I've seen that seem to imply that reinstalling WHS on a system, where the existing data pool drives are not ordered the same, can be problematic.  Is it true that WHS may not see the data properly in this case?

    No.  The problem is with the primary drive, not the secondary drives.  You can have the secondary drives in any order and it should still reinstall.  However, if the primary drive is not plugged into the first port on the motherboard, you may not get Server Reinstallation as an option.  However, if that occurs, all you have to do is change the order so that the primary drive is in the correct port.

    Say you change motherboards, or your sata controller(s), such that the drive orders change, is there metadata on the drives that tell WHS about all of the relationships of those drives for recovery?

    There is a reg file.

    Ultimately that's the big concern.  Imo, WHS should be designed that if you lose the primary drive and even recreate the entire system (but retain the data drives) you should be able to do a full recovery/reinstall with zero risk of data loss since the data is retained.

    That's how it is. :)  (And even if you can't get Server Reinstallation as an option, you don't lose the data.  Each drive is configured using NTFS and can be read by any computer that knows that file system.)

    If this is not true isn't it no better than raid?

    Thanks


    Thanks Kariya, that pretty much clarifies things for me.

    I have a couple of other questions for the group :)

    In cases where you have actual data on your primary drive (the "data" partition on the system drive), as long as duplication is on for all folders there's no chance of data loss if the system drive dies correct?

    As a follow on to that, and in light of your answers above, then it should follow that if you should lose your primary drive (system and first data partition as well of course) then you can do a full recovery simply by creating a new fresh WHS install and plugging in all your old data pool drives?

    This also begs the question, if you do lose your system drive and ONLY have the data pool drives can a NEW WHS install recreate all shared folders simply from the data on the data pool drives?   I assume yes, and that this information is stored in the drive "reg" file as you referred to it? 

    Lastly, if the tombstone files are lost (since you lost the primary drive) how does WHS know that two files on two datapool drives are actually the same file and not duplicate them on a new WHS install?

    Thanks!
    Monday, April 13, 2009 10:01 PM
  • In cases where you have actual data on your primary drive (the "data" partition on the system drive), as long as duplication is on for all folders there's no chance of data loss if the system drive dies correct?
    Correct. You're protected against the failure of any single drive in your server, as long as duplicaiton is turned on for all shares.
    As a follow on to that, and in light of your answers above, then it should follow that if you should lose your primary drive (system and first data partition as well of course) then you can do a full recovery simply by creating a new fresh WHS install and plugging in all your old data pool drives?
    A fresh Windows Home Server installation will not pick up the secondary drives from another installation; only server reinstallation (server recovery, for OEM units) will reconnect the secondary drives.
    This also begs the question, if you do lose your system drive and ONLY have the data pool drives can a NEW WHS install recreate all shared folders simply from the data on the data pool drives?   I assume yes, and that this information is stored in the drive "reg" file as you referred to it? 
    Yes, it can recreate the shared folders. The information is stored in the structure of the file system, by simply duplicating folders, shares, etc. in a particular manner.
    Lastly, if the tombstone files are lost (since you lost the primary drive) how does WHS know that two files on two datapool drives are actually the same file and not duplicate them on a new WHS install?
    The actual files, on all drives, are all stored in a (hidden) folder: <drive>:\DE\Shares\etc. Only tombstones are stored in <drive>:\Shares\etc. The server reinstallation process includes a pass through all of the secondary drives to rebuild the tombstones from the actual files.
    I'm not on the WHS team, I just post a lot. :)
    Monday, April 13, 2009 10:16 PM
    Moderator

  • As a follow on to that, and in light of your answers above, then it should follow that if you should lose your primary drive (system and first data partition as well of course) then you can do a full recovery simply by creating a new fresh WHS install and plugging in all your old data pool drives?
    A fresh Windows Home Server installation will not pick up the secondary drives from another installation; only server reinstallation (server recovery, for OEM units) will reconnect the secondary drives.
    This also begs the question, if you do lose your system drive and ONLY have the data pool drives can a NEW WHS install recreate all shared folders simply from the data on the data pool drives?   I assume yes, and that this information is stored in the drive "reg" file as you referred to it? 
    Yes, it can recreate the shared folders. The information is stored in the structure of the file system, by simply duplicating folders, shares, etc. in a particular manner.

    Thanks Ken.   I guess the two answers above have me confused as they seem contradictory, but I think for answer two (about recreation of shares) you are assuming reinstallation not fresh?

    So, here is my confusion.   In the scenario where you lose your primary drive and ALL you have left are your data pool drives, how does the server know to "reinstall/recover?"   Ie, I lose my primary drive, and a drop a new one in (no OS, no system data partition, nada) and it's plugged in as drive 0.  I have the data pool drives plugged in as well of course.   So, when I run the WHS installation will it see the data pool drives, and the new "primary" (empty) drive and go into recovery mode?   And if yes does it THEN proceed to "recover" share and file/tombstone information from only data on the data pool drives?

    In other words a full WHS system can be recovered only using the data pool drives assuming that the WHS installation is running in recovery mode?

    Thanks again.
    Monday, April 13, 2009 11:20 PM
  • I'm going to recommend you read the documents available here ; they probably answer a lot of questions you didn't even know you had.

    Server reinstallation is a special installation mode presented (in addition to new installation) if setup detects storage pool drives at the hardware detection phase. You choose whether to do a new installation, wiping all detected disks; or reinstallation, recovering the data on the secondary disks, and validating tombstones if present on the primary data partition.
    I'm not on the WHS team, I just post a lot. :)
    Monday, April 13, 2009 11:40 PM
    Moderator
  • A big reason for having RAID 1 on the server C: drive is the pain of reinstalling - not WHS itself, but all those little (or not so little) addons that have accumulated over time.
    qts
    Tuesday, April 14, 2009 8:11 AM