3rd drive as an offsite backup?

Has anyone used a 3rd drive as a ‘cold swappable’ offsite backup for a WD MBWE II set to Raid 1?  Swapping a drive out once a moth for an ‘offsite’ backup would be a great time saver.  Ideally, the device would rebuild the raid array behind the scenes.  The offsite drive could then be rotated the following month, etc… 


Haven’t myself…  however the rebuild time for a mirror is about 5 hours (MBWEII) regardless of the current amount of data to be restored.  Its a good idea in theory, and would likely work if you didn’t mind opening the unit up and cold swapping, then rebuilding at your specified intervals. 

The WD Share Space might be a better option as it allows it’s data to be backed up to an external USB drive.  This could be stored offsite and would avoid your having to dismantle and rebuild.  The rebuild time on either device is very time consuming.  :wink: 

Is the device/data inaccessible while a replaced drive is being rebuilt?  If not, then its ok if it takes 5 hours or so and I am fine with having to do it as a cold swap.  I love the power consumption of this unit and the built in raid.  But, I really need a simple way to move files to offsite storage, even if on a monthly basis.  Manually copying to an external device is doable but ideal.


I have just run a detailed and thorough (ish) testing of the ability for the WD MBWE II to mirror to a third drive and therefore create a 3rd backup / snapshot  to take off site …

… and I am pleased to say that it works like a dream.

You will need

you will need to buy a 1TB Caviar Green  WD10EADS drive


And something to connect the drive directly to your laptop to wipe it  (USB to SATA cable with power)


The download the latest copy of Western Digital Data LifeGuard Diagnostics


And you are ready to go …

I will post a tutorial and then post a link to the tutorial below this post.

I now have a lovely mirrored 1TB WD MBWEII with 2 off-site copies AND when I swap the drives to be mirrored I still have access to all the files and get to see the progress of the mirroring - excellent.

Tutorial to follow

So as we spoke it is necessary to ‘wipe’ before returning the previously removed drive back into the array?  I thought that would be an issue but obviously easy to overcome.  Great work!