sylvain> It's my fault too, because the mailing list doesn't accept
sylvain> HTML format.  And my provider doesn't offer plain text option
sylvain> with the mobile site :-(

It's a total pain at times.  I'm still reading email with plain ascii
most of the time, I don't care for HTML email generally since it just
gets in the way.  

sylvain> Back to the issue :

sylvain> I have stop the raid.
sylvain> mdadm --stop /dev/md2
sylvain> mdadm: stopped /dev/md2

sylvain> cat /proc/mdstat
sylvain> Personalities : [raid1] [raid6] [raid5] [raid4] 
sylvain> unused devices: <none>

sylvain> And when i try to re-assemble, the command is aborting :
sylvain> mdadm --assemble --force /dev/md2 /dev/sd[bcde]1
sylvain> mdadm: /dev/md2 assembled from 2 drives and 1 spare - not enough to start the array.

So if I look at the event counts, there's a mismatch between
/dev/sd[bde]1 and /dev/sdc1.  So let's try to assemble without /dev/sdc1:

  mdadm -vv --assemble --force /dev/md2 /dev/sdb1 missing /dev/sdd1 /dev/sde1

and see what happens then.  With three out of the four devices, the
RAID5 array should start up, and then you can add in /dev/sdc1 to
rebuild the parity.

John