HowTo: snapraid and Drivepool on Windows Server 2012 R2 Essentials

It took me some time to fully understand how snapraid works. Even though it’s quite simple. Similar to unraid, parity is calculated and stored on one (or more) parity disks. Each data disk uses a normal filesystem and you can just pull it out of the Server and mount it somewhere else. So far so good. But instead of using the whole disk, snapraid works on a file basis. Meaning it works on files and folders and not necessarily the whole disk. In the snapraid.conf you have to specify the watched folders or mount points.

The question was then: does snapraid work with Drivepool (or similar pooling application) and how do I configure it? Well of course it does work with Drivepool, but you don’t point it to the Drivepool but to the physical disks directly. You also don’t need to point it to the hidden drivepool folder, just the root of disk is fine too (if you want to use the whole disk). Just be sure to use the default values for #nohidden (you don’t want that enabled!) and it’s probably a good idea to use the default exclude list.

Example with one OS drive (C:), three data drives (D:,E:,F:) and one Parity drive (G:)

parity G:\snapraid.parity

content C:\snapraid\snapraid.content
content D:\snapraid.content
content E:\snapraid.content
content F:\snapraid.content

disk d1 D:\
disk d2 E:\
disk d3 F:\

# Excludes hidden files and directories (uncomment to enable).
#nohidden

For the rest keep the defaults.

Now on to the configuration of Drivepool. Put all your Serverfolders on the Pooldrive. You can change the Pooldrive drive letter using Computer Management, just as you would with a normal harddrive. In Drivepool you want to switch off drive balancing, because you don’t want data to be moved from one drive to another.
drivepool balancer
Rather configure file placement based on folders. For example allow your movies to go on any of the three drives, but limit other folders to one drive. It will still move to another drive if the current one is too full (you can configure this in the file placement as well).
drivepool file placement

For snapraid there’s a great helper script out there for Windows Powershell: https://snapraidhelper.codeplex.com/
Be aware there is another old version around as well, but this one if the extended one from therealjmc. It’s also well documented.

To run snapraid helper script using the task scheduler you might want to check out this page: http://community.spiceworks.com/how_to/show/17736-run-powershell-scripts-from-task-scheduler

I configured my two tasks. One that runs the helper script daily (except on Sundays) without parameters and another task that runs only once a week (on a sunday, duh) with the syncandscrub command. The 2nd task also wakes up the server and since I use lights-out it will monitor snapraid.exe and puts the server back to sleep again once it’s finished.
snapraid task scheduler

6 thoughts on “HowTo: snapraid and Drivepool on Windows Server 2012 R2 Essentials

  1. Hi, thanks a lot for this! Any major downsides to using the GUI (http://elucidate.codeplex.com/) stand-alone add-on? I’ve gone through the steps to restore when a failure happens and was terrorized by the command line wizardry needed!

    I think I’m convinced that using SnapRAID will be much better long-term than DrivePool’s own duplications, though I’m usually much more inclined to save money than time. I keep bouncing back and forth between the two options of DP+duplication and DP+SnapRAID. The thing that I’m most worried about the latter is the recovery steps and where might I go to look for support if I can’t really sort things out. On the other hand, if I ever want more than 1-drive-failure protection with DP+duplication, that means I’m sacrificing 66% (?) of my total storage.

    • Hi,

      I haven’t tested this GUI yet. In fact I didn’t even knew about it. But my current setup performs with the Windows Task Scheduler and Powershell Scripts just fine. I haven’t tested a restore recently, but from my tests before I switched to snapraid, it was rather easy. However I only tested the case that a complete harddrive failed and had to be replaced. If we are talking about individual files, then it might be more complicated.

      If you use DrivePool and Duplicate your data, then you need twice the size for your data since every piece of data will be duplicated on (at least) two physical disks. Snapraid always only takes one (or more) separate disks to store parity information. So if you have 4 disks, you can use 3 for storage and 1 for parity, whereas with DrivePool you only have two left for storage. You just should not combine DiskPools (automatic) duplication, or rather it’s automatic moving function with snapraid. Since DrivePool might move data from one disk to another and to snapraid it looks like some data got deleted and some got added. If you delete data without updating your parity right away, you will be unable to restore (adding new data is harmless, but that data is unprotected until you update the parity).

      So I’d recommend that you duplicate your very important files, or better yet, have another backup of those off-site in the cloud, deactivate the automatic balancing and then use snapraid on top of it. If you ever need help with snapraid the official forums on sourceforge will be the place to look for it.

    • Glad to know that my post was helpful. I am still using the same configuration and it is working perfectly for my needs. Never touch a running system. I only did update snapraid from time to time which is easy enough (just replace .exe file).

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