On Wed, Oct 6, 2010 at 12:48 PM, Les Mikesell <lesmikesell at gmail.com> wrote: > On 10/6/2010 2:36 PM, Aleksey Tsalolikhin wrote: >> >> # mdadm /dev/md0 --add /dev/sda1 >> mdadm: Cannot open /dev/sda1: Device or resource busy >> # >> > > Do you still have it mounted as you mentioned above? If so, unmount it. *Facepalm* That was it. Thank you. /dev/sda1 is back in /dev/md0 and reconstruction is in process. > If it shows as 'failed' in /proc/mdstat you would have to use mdadm to > remove it before adding it back. Ah! Got it, thanks, Les! Aleksey