F16 occasionally breaks RAID1 (md) on boot

Thu Feb 16 02:00:31 UTC 2012

On Thu, Feb 16, 2012 at 01:49:17 +0000,
  "Andreas M. Kirchwitz" <amk at spamfence.net> wrote:
> 	Hello users of Linux software RAID!
> 
> I have two identical harddisks, and on a freshly installed Fedora 16
> all my filesystems (/boot, /, /home, /usr/local, /opt, swap) are set up
> as software RAID1 (md).
> 
> Occasionally (about every second boot), Fedora 16 silently removes
> one of the mirrors from the RAID1 devices. Sometimes this happens
> for just one device, sometimes for up to three. So far, it never
> happened to "/boot", "/" and swap but only to "/home", "/usr/local"
> and "/opt".

It's probably worth checking that /etc/mdadm.conf looks good. If it doesn't,
fix it and then rebuild your initramfs.