# Hardware RAID - Dual Boot



## badhat101 (Mar 12, 2011)

I'm looking to build a dual boot system with FreeBSD and Windows 7 using 4 Western Digital RE4 drives. The motherboard that I'll be using is the Asus Sabertooth P67.

Now, from what I have read from some googling and this it seems that the Asus board supports hardware RAID without me having to buy an expensive SATA controller. And, if my understanding is correct, hardware RAID should outperform software RAID and this is the reason that I prefer it. 

If I correctly set up RAID through the BIOS on the motherboard, will the FreeBSD installer need some special input to make RAID work or is hardware RAID completely transparent to the OS installer? I would like to dual-boot and I plan on allocating 1/2 of each drive to FreeBSD and 1/2 to Windows 7 through partitioning-- though I am unsure of how to do this. I don't know if anyone here knows how to do that, but is anyone aware of whether the Asus board really does have hardware RAID or is the Intel Rapid Storage Technology simply software RAID that requires winmodem drivers? And will the FreeBSD installer see the drives in RAID and "just work" or will it require some tweaking in the installer?


----------



## mav@ (Mar 12, 2011)

Most of on-board RAIDs (including that Intel one) are software and so not transparent. FreeBSD has driver named ataraid(4), supporting several kinds of them. Unluckily at this moment that driver is not in the best shape (not very reliable). I am now working on replacement, but it will take few more months to complete it.


----------



## phoenix (Mar 17, 2011)

If you plan on using each OS roughly equally (ie, half the time booted into Windows, half the time booted into FreeBSD), then I'd suggest dedicating two full drives to each, and configuring them using the software RAID tools that come with the OS.

For example, use the BIOS-based "hostraid" to create a mirror using 2 drives.  Use that to install Windows 7.

Then use the other two drives, individually, to create a gmirror(8) based RAID1.  And install FreeBSD onto that.


----------

