The only issue is that the md code only auto-scans non-MD partitions when assembling a RAID array. You can use mdadm at boot time to put them together as other people have shown, or you can add an option to the kernel command line (LILO append="..." option; other boot loaders have something similar) to help it out. Since I have my root partition on RAID1+0, I have "md=4,/dev/md2,/dev/md3" on the kernel command line. This gets /dev/md4 (which is a RAID-0 made of two RAID-1s) going. Oh, regarding data placement: I also have the RAID-1 split across controllers. Also, I have half the mirror in removable drive trays for emergency insta-backup (fire or other natural disaster) uses. There are uses for such things. - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
