Nigel Kendrick wrote: > 2) As part of the testing, I rebooted the system with the second drive > pulled out, the whole lot then boots and I can use mdadm -a to add the > second drive to the mirrored pair. The drives resync at a decent speed and > the pair works fine for the duration, but when I reboot the second drive is > not part of the mirrored pair unless I manually add it again. What's the partition type on the second drive? If you want kernel to start software RAID device on boot, all partitions that are component of such devices must be tagged as "linux raid autodetect" (type fd). You can use fdisk to easily check (use "p" command) and set (use "t" command) this. -- Aleksandar Milivojevic <amilivojevic at pbl.ca> Pollard Banknote Limited Systems Administrator 1499 Buffalo Place Tel: (204) 474-2323 ext 276 Winnipeg, MB R3T 1L7