On Wed, Jan 27, 2010 at 8:12 AM, Robert Howard <rjh0507@xxxxxxx> wrote: > Yes, you should be able to do it either way. I have built 6+ drive arrays > from clean install before without any problem. > > IIRC, the command should just be mdadm /dev/md0 -level=5 -raid-devices=4 > /dev/sd[a-d]1 > > You can also add a switch to force all drives active but you must also add > -ff to the command line. So according to everyone who is supporting this thread, I should be fine with the following command assuming that all 4 individual disks have an identical 'fd' partition, correct? mdadm --create /dev/md0 --level=5 --raid-devices=4 /dev/sda2 /dev/sdb2 /dev/sdc2 /dev/sdd2 The above command is what I am running and I will try it again on my test machine just for the sake of resolving this. I DON NOT want the 4th disk to be a 'hot spare' but rather an expansion of the RAID5 array to allow for more disk space / redundancy. I think the 'mdadm' utility has a 'grow' option to do the same thing to an existing RAID system if I had only 3 drives to RAID5. Let me know if anyone sees an error in my command syntax and thanks again for all your help!
