At the moment mdadm with imsm metadata is totally broken on xenial (and I suspect on all ubuntu distros with systemd). Due to incorrect ordering of things at shutdown machines with arrays assembled at boot with mdadm and imsm metadata may hang and the array is resynced everytime even if the bios shows it being in a normal state.
See bug 1320402, bug 1587142 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1028677 Title: mdadm should be used for fakeraid (instead of dmraid) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/debian-installer/+bug/1028677/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
