Sep
23
WHS - Out of Space?
Filed Under Computers, Home Server, Projects
I ran into my first real issue with Windows Home Server last week. When I first setup my WHS, I configured the machine using a single 1TB drive. I did this thinking that I would test out the WHS and verified that I liked it, before formatting all of my other hard drives and losing their content. This also provided me with a migration plan of adding 1 HDD at a time. A good plan, right?
Wrong! Apparently by upgrading using this method I found one of the flaws in Microsoft’s Drive Extender technology.
Drive Extender makes your multiple drives appears a single drive, similar to JBOD, but they actually still separate drives, and files are not spread across multiple drives. It also has the ability to do mirroring of files across multiple drives.
The one key to this system, is that at any given time, the largest file that can be stored is whatever free space is on the first primary drive (the one you install on). This is why it is recommended that you install on at least a 500GB hard drive, because WHS must copy the file to this “swap” space first, and then balance it across your remaining free hard drives.
Under normal operations, WHS will try to use your additional hard drives first, and save that hard drive for last. So normally you would be able to copy a 500GB file if needed.
In my case, I started with 1 drive and filled it up. So it filled up the entire primary drive. When I added additional drives, drive extender automatically “balanced” 20GB’s off of the primary drive. Apparently that is the default for balancing, it will always try to free 20GB’s only.
Most people would never run into this assuming you always added drives before your last disk was full. Since I filled mine up, the largest file I can now add to the system is a 20GB file, because that is all the free space I have on that drive. When I try to add a file larger than that, I get an “out of space” warning, even though I technically have over a terabyte free.
Again, most people would never have this be a problem, except that I am trying to archive a couple VHD images that are over 20GB. So currently I am at a stand-still of what to do.
You can’t just force the primary drive to clear more space?
If there is a way, I haven’t found it yet. I do have a couple ideas I am going to try tonight. I will post more tomorrow with results.