QEMU to Support Software RAID under Windows?
 

I know, this is borderline, but figure this is the group of folks who might know. I do a lot of audio and video stuff for myself and my family. I also have a rather unusual networking setup. Long story short, when I try to run Linux as my primary OS, I usually end up reinstalling Windows after a couple weeks because there are still holes in what I can do. That isn't the fault of Linux as much as folks who write device drivers or have video codecs that require DirectShow.

However, the big thing I really miss from Linux that keeps me trying to find a way to convert is the support for Software RAID 5.

It occured to me yesterday that perhaps the trick would be to use QEMU to run Knoppix or Damn Small Linux under Windows, and then setup a RAID 5 array under one of those. Not to mention then having access to Linux for some other fun stuff.

I'm not sure if that's even possible, and if it is, how much trouble I would have moving files around to and from the RAID array if it's setup that way. So I'm wondering if anyone on here has ever tried this?

TIA,
Ewan

One other idea I've had (and y'all can tell me how much I'm showing my lack of knowledge in this area) is to try recompiling the mdadm and other tools using cygwin. But I assume that this is an idea that's been floated before and didn't work since I haven't seen any signs of this having been done before.

Just to fill y'all in, here are my alternate options:

1) Convert completely to Linux
- Pros: Philosophically this is my preferred choice, and I know that RAID would work under this
- Cons: I have a DLink DWL-G520 PCI card that according to the Ndiswrapper wiki would require at least a daily reboot. I also would lose the ability to decode recordings that I transferred from my TiVO using TivoToGo which would require me to do recordings from my box - and then I couldn't record anything from our digital channels (no cable box up here)

2) Convert completely to Windows
- Pros: This is where I currently am anyway, so no effort :-)
- Cons: At the current rate of acquiring home videos (20-30 Gigs a month because my middle daughter's handicapped - and so there's a lot of stuff we tape from school and other places so she can watch them over and over again), my photos (a gig or two every month), and backing up our music and DVD collections (middle daughter is rough on disks because she doesn't understand she shouldn't be), I would need to continue to buy one 250 Gig HD every six months, and a second 250 Gig HD in that period to allow me to do a poor man's mirror of the first disk. And I'm already having to use one of my backup disks because that's still a bit expensive, and I know if I kept that up I'd soon be out of USB ports.

3) Dual boot
- Pros: Gives me the same capabilities I'm looking for by trying to get Software RAID running under windows
- Cons: Typical dual boot "fun" of having to reboot when I have to change acitivities, and so long transfers from the TiVO would reduce the time when we could view anything I had backed up on the RAID array.

FWIW,
Ewan

Based on the lack of response, is this a really dumb question and I'm just not seeing why, or is this just so far out there that no one else has tried this already?

TIA,
Ewan

Well qemu emulates a computer. So it sets up pretty basic PC. It doesn't use your hardware itself. There might be an option to do that but I don't know. Maybe you can find anything on the qemu forums or documentation.

edit: qemu can use your hard disks itself but it's not really recommended I think. Also what's the difference between getting it to work under a linux emulated by qemu and running linux itself? Apart from that you can now have both windows and linux on at the same time it won't help much in fixing the problem I'd say.

I also found this. Apparently redhat can do RAID5:
http://www.redhat.com/docs/manuals/l...ware-raid.html

So it should be possible with other distros though the software might be only in redhat I don't know about that but you might want to check it out.

Could you point me to the information you found on this? Even if it isn't the recommended solution, it may give me insights into how to do what I want to do. For example, from what little I've read on this so far, I "should" be able to create a QEMU image file that's about the same size as my HD, and then access that. But I'm a little nervous about what would happen when I tied them together as a RAID array.

For me that IS the problem. That I have some things that I need (or at least prefer) to do using Linux, and some things I need (or at least prefer) to do using Windows.

I have also thought about setting up Linux and then using QEMU to let me run Windows in it, but since the biggest problem I currently see for running Linux is with the networking, and if it doesn't work in Linux it isn't going to work for the virtual Windows machine, then that seems to be the less preferable solution.

Thanks for the help,
Ewan

I managed to get this working, although I had to use coLinux rather than QEMU to do this.

All the pertinent info can be found at:
http://a1.blogspot.com/2005/08/step-...aid-using.html

Hope that folks find this helpful!