Comment 22 for bug 990913

I have the same issue.

The problem is that the /usr/share/initramfs-tools/scripts/mdadm-functions
Is called before all drives has been initialized.
I have 6 drives in RAID array. 2 of them are onboard SATA and 4 are on mpt2sas (SAS2008) card.

Apparantly mdadm tries to initialize the array before all 6 drives have been attached to the system

If i edit mdadm-functions to this everything works (ugly fix):

degraded_arrays()
   {
       sleep 15
   >---mdadm --misc --scan --detail --test >/dev/null 2>&1
   >---return $((! $?))
  }

This bug was introduced for when i upgraded from 10.04 LTS to 12.04.1 LTS Today!