Note: "Installing mdadm package from Ubuntu 16.10 fixes the problem." is probably incorrect. It seems that the above steps cause boot to fail even aftern installing mdadm version 3.4.
** Bug watch added: Debian Bug tracker #784070 http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=784070 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1700921 Title: Boot with degraded RAID5 still fails on Ubuntu 16.04 LTS To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/mdadm/+bug/1700921/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs