Luca Berra <bluca <at> comedia.it> writes:

On Sun, Nov 14, 2010 at 05:36:38PM +0200, Zoltan Szecsei wrote:

quoted

*If I have to reformat the drives and redo mdadm --create, other than mdadm 
stop, how can I get rid of all the /dev/md* etc etc so that when I restart 
this exercise, the original bad RAID does not interfere with this new 
attempt?

mdadm -Ss
mdadm --zero-superblock on each partition

quoted

*Partition alignment?
Is this relevant for modern HDs (I'm using 5900rpm Seagate 2TB drives)

for modern hdds with 4k sectors it is
new fdisk and/or parted should already know how to align
in any case, since you want to use the whole space for raid, why create
partitions at all, md works nicely without

Hello,
first thank you for the interesting topic (because it fits my questions ^^) and 
for all the participation of this community to this topic !
 
I've read somewhere (sorry I can't remind it) that the raid still could be 
unaligned by using the whole disk, and so we had to create a partition aligned 
(by using fdisk -u, then creating a partition beginning at LBA 64 at least, and 
that would span on a length multiple of 8.

Was it totally wrong ?

Tanguy