Re: mdadm --detail output: 2 questions

On Thursday April 22, sandro.dentella@tin.it wrote:

Hi all, 

  I made a raid5 array with command

   mdadm -Cv /dev/md3 -n5 -x1 -l5  /dev/sd{a,b,c,d,e,f}1

  It took me a while to undertand that while syncing a raid5 mdadm --detail
  marks as failed the spare disk + 1. Is that correct? here the output before
  it was finished and afterwords. The last one really was produced by mdadm 1.5,
  the first one by mdadm 1.2, since 

Yes. That is correct.  Rebuilding a drive is faster than correcting
all parity blocks, so mdadm prefers that approach.

##########################################################################

in both output I see 7 'Total devices' and 1 Failed but I don't have any
failed in reality nor in the last part of the output. Am I misunderstanding
the output? 

No, the kernel isn't quite keeping track of things properly.

Last question: what is the meaning of  'Events: 0.2' (0.1 during
syncing)?

Just a sequence number of superblock updates.

NeilBrown