I meant to post this a while back, but its been sitting in my queue. Back in February I purchase a x335. After some trials I got mpt-status and native hardware RAID functional under XEN. Although, testing the performance is still on my TODO list. Then April I got a x206 to replace a x205. The x206 said it had RAID 1 built-in with linux drivers, and thus didn’t require an additional RAID card. I should have recalled that linux drivers, most often for RAID means Redhat only binary drivers.
There wasn’t much out there, but after several long google sessions, I discovered this short singular reference, Adaptec 29320 with HostRAID:
Adaptec HostRaid is software raid.
There is some binary drivers for RedHat/SuSe, no Debian.
No opensource drivers aviable.
If you need software raid, why not to use one bundled with kernel? Or maybe lvm?
Imho much more better solution is to buy “real” raid card, or not to use raid at all.
Given the time frame I had, after wasting a few days trying to get it to work without the drivers and before finding that comment, I decided to just use the Linux md software raid driver instead. Maybe getting a hardware raid card at some later point. Note, if you use Redhat the drivers are available here. There are also some comments in this discussion: Debian on Dell Servers, Parity Networks: Debian and the Adaptec AIC-7901A (HostRAID) Controller and Installing Debian 3.0 (woody) with Adaptec HostRAID support.
Finally, I used some of the information in these two articles to get Xen booting on a md root device: [Xen-devel] Debian Sarge Root Raid + LVM + XEN install guide (LONG) and
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/md1 3989824 1896640 2093184 48% /
tmpfs 62476 4 62472 1% /dev/shm
/dev/md0 466596 34382 407322 8% /boot
nic@sea:~$ cat /proc/mdstat
Personalities : [raid0] [raid1] [raid5]
md1 : active raid1 sdb2 sda2
4000064 blocks [2/2] [UU]
md3 : active raid1 sdb4 sda4
66685696 blocks [2/2] [UU]
md0 : active raid1 sdb1 sda1
497856 blocks [2/2] [UU]
unused devices: none