Hi, I'm trying to do something that seems to have needed a lot more pizza than anything I've tried before, am I missing something? Using a new Promise ATA66 card I'm trying to build a fast IDE based array. I've had to compile a development kernel (2.3.13) to get my redhat based linux to recognise the card, so far so good, I can see the drives (hde, hdf and hdg - yeah, performance hit from 2 drives on one IDE) and have been able to mount them individually. I've written a nice raidtab but mkraid aborts when I try to build the array. I've dug in a little, I seems to bomb when doing the SET_ARRAY_INFO ioctl with an errno 22 (EINVAL - invalid argument). Any suggestions? Thanks, Ed #/etc/raidtab raiddev /dev/md0 raid-level 5 nr-raid-disks 3 nr-spare-disks 0 persistent-superblock 1 parity-algorithm left-symmetric chunk-size 32 device /dev/hde1 raid-disk 0 device /dev/hdf1 raid-disk 1 device /dev/hdg1 raid-disk 2