[CentOS] RAID-1 strategy for a CentOS/Xen server?

Hi,

I'm planning to migrate my current server configuration:

AMD Athlon/X2 FreeBSD 62-Release 2 x 250GB HW RAID1 (all partitions RAIDed, incl. swap)

to a Xen/CentOS config:

AMD Athlon/X2 Dom0 CentOS 51 Xen 31 Dom1/1 FreeBSD 7 Dom1/2 CentOS 51 ...

To "best preserve" RAID1 mirroring protections of OS, Data, etc

*AND*

optimize performance, how should I setup RAID for the "new" configurations?

Should DOM0 be RAIDed?

Each DOM1, as well?

Should I continue to use HW RAID or switch to SW? A mix?

I understand I can do any/all ... choosing the "right" option is the goal, here.

Advice is appreciated.

Regards,

Bob Tompkins