Is there a Linux software RAID that can be shared with a windows installation?

Solution 1:

You have 3 "models" of RAID, and 3 answers to your question:

  1. The hardware RAID: It should work on Linux and Windows, and it's transparent and makes everybody believe there's just one drive (if you're doing RAID1 for example).
  2. Semi-hardware RAID(or FakeRAID): In fact it's in reality 99% software RAID. Take a look at the FAQ about it. If you have a driver for Windows AND Linux, it's mostly OK.
  3. Software RAID. I don't know any software that is compatible between Linux and Windows, so it's a no.

Solution 2:

dmraid should be able to do this. dmraid is the driver for so called "FAKERAID" solutions you on lots of motherboards these days, chipsets that offload all their work to the CPU.

I can't guarantee it will work though. You'll need a supported dmraid chipset, some disks and a cross-platform filesystem to test it... And I seriously suggest you do test it before investing any data into the setup.

As far as filesystems go, NTFS support in Ubuntu is much better than ext-n support in Windows. At least it was the last time I checked.