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  • Question

  • Why does WHS recommend not to mirror or stripe the hard drives?

    How does WHS handle this if it doesn't?

    I have one 80 gig drive and two 200 gig drives.  What happens when one 200 gig drive fails?

    I know it utilizes snap shots but i would like to know more.

     

    Monday, March 5, 2007 1:21 PM

Answers

  •  malbrosia wrote:

    Why does WHS recommend not to mirror or stripe the hard drives?

    How does WHS handle this if it doesn't?

    I have one 80 gig drive and two 200 gig drives. What happens when one 200 gig drive fails?

    I know it utilizes snap shots but i would like to know more.


    WHS includes a technology called Drive Extender. It offers the ability to designate individual shares as duplicated (mirrored) on another drive. Unlike RAID 1, this doesn't require two identical drives, it could be any two drives in the WHS machine (or connected by USB/Firewire/eSATA).

    In your scenario, assuming you have all shares set for duplication, if one 200 GB drive fails, you go into WHS Console and remove it. Then, if it's internal, you shut down, replace it, and start back up. If it's external, it's possible that you can hot-unplug to replace it. You then go back into WHS Console and add the new drive to the storage pool. Drive Extender takes care of the rest.

    It's similar to software RAID 1, but more granular and flexible. In addition, DE load balances your disks, to aid in performance and reduce the chances of data loss.

    As for RAID 0, why would you use RAID 0 on a file server? When you lose any 1 drive in the array, you lose the entire array.
    Monday, March 5, 2007 9:36 PM
    Moderator

All replies

  •  malbrosia wrote:

    Why does WHS recommend not to mirror or stripe the hard drives?

    How does WHS handle this if it doesn't?

    I have one 80 gig drive and two 200 gig drives. What happens when one 200 gig drive fails?

    I know it utilizes snap shots but i would like to know more.


    WHS includes a technology called Drive Extender. It offers the ability to designate individual shares as duplicated (mirrored) on another drive. Unlike RAID 1, this doesn't require two identical drives, it could be any two drives in the WHS machine (or connected by USB/Firewire/eSATA).

    In your scenario, assuming you have all shares set for duplication, if one 200 GB drive fails, you go into WHS Console and remove it. Then, if it's internal, you shut down, replace it, and start back up. If it's external, it's possible that you can hot-unplug to replace it. You then go back into WHS Console and add the new drive to the storage pool. Drive Extender takes care of the rest.

    It's similar to software RAID 1, but more granular and flexible. In addition, DE load balances your disks, to aid in performance and reduce the chances of data loss.

    As for RAID 0, why would you use RAID 0 on a file server? When you lose any 1 drive in the array, you lose the entire array.
    Monday, March 5, 2007 9:36 PM
    Moderator
  • I happen to have a PCI-based Promise PATA RAID 1 controller which will work as a standard IDE controller too.

    This controller will run RAID1 on two identical PATA drives. This seems like an obvious place for the first drive in a WHS scenario. However I have not even sought out the existance of a W2003 signed/otherwise driver for the adapter (would need F8 during text install phase).

    The hardware handles the underlying disk behavior, and WHS should see one drive. Additional HDDs could be added to other MB controllers and be used normally under WHS control. BIOS would need to be told which controller to favor at boot time.

    I have not tested this, but have considered it since I happen to have the adapter and several identical HDDs around. I'm sure the final WHS product will not appear in a config like this.

    Comments?
    Wednesday, March 7, 2007 1:24 PM
  • jgenevea - I had the same thoughts about primary drive raid 1.

    I have a test build in progress with a single drive. Was considering rebuilding the setup by running the primary drive as a hardware raid1, then letting WHS cover redundancy with additional drives.

    Thursday, March 8, 2007 4:08 AM
  • Ken,

    I am assuming that Malbosia was talking about RAID 5 (striping with parity) when they asked about striping. I am highly concerned about the potential data loss that could occur from loosing a drive.

     

    My test server has 4 x 300GB drives in it, and 2 x 120GB drives. It was previously running Windows 2003 Server Standard with the 2 x 120GB drives as a mirrored set for the OS and the 4 x 300GB drives in a RAID 10 format (very high tolerance, lots of wasted space).

    I would like to see something silmilar to RAID 5 be implemented by Drive Extender. I would like to be able to seamlessly pop in a replacement drive and have WHS rebuild it for me. Also, when you loose a RAID 5 drive the RAID controller can calculate the missing data on the fly, this allows for continued use of the deteriorated array for backup or regular use (although it is MUCH slower).

    Does Drive Extender utilize any sort of compression when it duplicates? Or are we loosing twice as much space by duplicating versus a solution like RAID 5 which consumes one full drive for parity?

     

    Thank you.

    Saturday, March 10, 2007 6:37 PM
  • Daren, I understand the advantages of RAID arrays for the technically sophisticated (savvy) user. However, WHS is targeted at households with more than one computer and a permanent broadband connection to the internet, and Microsoft's market research has shown them that those households are predominantly not savvy users. So they have decided that RAID will not be a core component of WHS; it will not be built in.

    Drive Extender offers the benefits of RAID 1 where a user wants those benefits, and has the same costs, on a file basis, that RAID 1 does on a drive basis. In addition,it makes for much easier adding, removing, and especially upgrading drives than any RAID solution I'm aware of (that's targeted at the consumer market). So it's a net win, in my opinion.

    For the user who wants RAID anyway, you can always buy a RAID HBA that has Windows Server 2003 drivers available and roll your own. Microsoft has said "RAID is not a supported scenario" but I don't think that means RAID doesn't work, it just means that they aren't going to supply it, and they aren't going to help you dig yourself out of a hole if your RAID HBA dies and you can't get at your data any more. I had it happen once; fortunately the manufacturer has used the same on-disk architecture for years, so a new (different model) controller got the array back up and running. And it's a much larger problem for chipset or onboard RAID HBAs.
    Saturday, March 10, 2007 8:22 PM
    Moderator
  • Hello,

    I have just done my first install with new hardware. I have got 2x 400 Go HDD. Windows home server console reports a total size of 745 Go. I have done 3 backup from 3 differents computers for a total of 139 Go. Free space is 596 Go. Does it mean that PC backup are not in a " Raid 1" mode ?

     

    Saturday, March 10, 2007 8:36 PM
  • That's correct. Microsoft decided that backups are already spread across more than one disk, by virtue of being on two different PCs. So the backups aren't duplicated.
    Saturday, March 10, 2007 8:56 PM
    Moderator
  •  

    A storage server that doesn't support RAID. Only from Microsoft...
    Wednesday, October 24, 2007 4:41 AM
  • Well, it is for a plug and play appliance. Could you tell me how many people who aren't technically proficient will be in a position to set up and rebuild a Raid array? The majority of consumer motherboard integrated raid solutions just mean that people are as likely to loose access to any data, as they are anything. Most of the external Raid boxes use proprietry software on their own hardware, which if either fails, you loose the lot.

    Drive extender as a technology has a lot going for it, can use any type of drive of any size and with any connection. Can be added/removed with little or no problem and a failure can be just replaced and the technology will take care of rebuilding.

    A few generations down the line, I can well see this technology creeping into other operating platforms.

    What I would like to see, is DE become an 'open' platform, as I'm sure it would find many uses in storage applications.

     

    Colin

    Wednesday, October 24, 2007 5:02 PM
  •  

    Don't forget the target for WHS...

     

    The target user for WHS is a home user, but how many home users will be setting one up?

    The target market for WHS software sales is the system builder market, which consists of technically proficient members.

     

    I think the issue is that the official stance that RAID is not supported sounds bad to the market that Microsoft is selling to. I think that RAID needs to be officially supported as an advanced option. I will be installing a WHS server for my parents when it is released. I will be setting up a RAID 1 array as the OS drive, and either using DE over regular drives, or using DE over RAID 1 sets... I am not sure yet.

     

    DE is a great, easy to use alternative to RAID, however, it is not a replacement by any means. For techincally proficient people, such as myself, that have relied on RAID for years, and not been dissappointed... it is hard to rely on DE for ourselves, or our families. The main reason for this is that DE is not established and not proven yet.

     

    I agree with MS that DE is a better solution for a residential market, however the sales of the software are targeted to technially proficient users. Because of that, DE should be the standard option, and for advanced users, there should be an option to choose between RAID, DE, or DE over RAID. This way everyone is taken care of.

     

    My largest fear for WHS right now is that MS will remove the ability to install to a RAID 1 array by changing the setup to not allow normal 2003 Server drivers.

    Wednesday, October 24, 2007 7:42 PM
  • It's targetedto people like HP and Fujitsu - there is NO WAY they are going to put in the extra finance and resources that a Raid Setup would require, they are building to a price!

    Try explaining to the purchaser, " well, yes, the Microsoft software duplicates all your data across all the drives in your system, however, we don't believe it and are fitting extra hardware and drives beacuse"

    The purchaser will hear the last few words as they are walking out the door.

    Also, do you really think Microsoft is going to be happy with a system builder who does this? - No Way.

     

    Colin

    Wednesday, October 24, 2007 8:14 PM
  •  

    Colin,

     

    RAID is very inexpensive, hard drive prices have dropped dramatically in recent years, and almost every SATA chipset that support more than one port supports RAID. I fail to see how to cost would be affected.

     

    WHS does not have any protection for the OS drive. DE is only for drives used for storage. I am sure there are options for backing up the server, but a RAID 1 array with alerts would enable the server to survive a lost OS drive.

     

    Every PC I have built for the last 5 or so years has had a mirrored OS drive. The array has saved me many times over that period. It's a lot easier for me to walk my family through swapping a hard drive out than it is to walk them through re-installing the OS.

     

    Granted, these companies will have restore discs, but all the customizations will be lost, such as users, their SIDs and share permissions will all have to be re-established.

     

    Also, I don't think that MS will care if a system builder says that they prefer to use RAID over DE... MS is still selling their product either way. Microsoft only cares about the bottom line when it comes to system builders, MS is a company too, and the main reason a company is born is to make money.

     

    Just for the record, I am not against the technology behind DE. There are many uses for this type of technology. I think it is a great way to protect particular files and folders which helps you maximize the amount of wasted space versys a RAID array. However, with that being said, RAID 1 and 10 give the maximum amount of redundancy that I personally want with my home server. I will be using a RAID 1 array for the OS, it is a tried and proven solution that will cost me another $45 for a second drive (Retail cost, my MB already supports built in RAID on the SATA ports). I will also be placing hot-swap bays on the front of the unit so I can easliy walk someone through the replacement of a drive. If I was building a home server for the general market, I would do the same, much easier for tech support to overnight a new hard drive caddy (with new drive) then have the customer pop the bad one out, pop the new one in and start the rebuild process. Much less time consuming than walking them through a restore after a new drive was installed, then walking them through either a re-configure, or restoring from a backup (I assume that HP and the others will have a backup program to back the confuguration up nightly or so)...

     

    Again, that is just my opinion, being in the industry and dealin with issues like this on a daily basis. Not only do I need to keep the initial cost of the hardware down, but I need to minimize the support costs as well.

    Wednesday, October 24, 2007 9:56 PM