Multiple Software RAID problems on 14.04.2

[Gareth Evans]

edit:
NB. this report is inaccurate - please see the following instead:
https://bugs.launchpad.net/ubuntu/+source/mdadm/+bug/1469269

Re. mdadm 3.2.5-5ubuntu4.1 (or possibly kernel bug(s)?)

Firstly,

/etc/initramfs-tools/conf.d/mdadm does not seem to exist as it is suggested it should in the official server guide.

1. Encrypted LVM RAID fails to boot
2. LVM RAID fails to boot when degraded

I have had various issues re. (2) tested with VirtualBox and KVM (with and on 14.04.2)

(1) gets so far in the boot process then keeps displaying "No volume groups found"
(2) if virtual disk is removed from the VM, I've managed to get it to boot once and remove the offending disk from mdX using mdadm ... but couldn't reproduce this behaviour a second (or third) time - now it just keeps printing...

Incrementally starting RAID arrays...
mdadm: CREATE user root not found
mdadm: CREATE group disk not found
Incrementally started RAID arrays

...every few seconds.

That symptom seems to be fixable in other reports in circumstances where the system is bootable after a soft reset (Ctrl+Alt+Del) but no such luck in my case.

It seems that software RAID is a mess in 14.04 - can someone take a good look at it?

[Ubuntu Foundations Team Bug Bot (crichton)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It seems that your bug report is not filed about a specific source package though, rather it is just filed against Ubuntu in general. It is important that bug reports be filed about source packages so that people interested in the package can find the bugs about it. You can find some hints about determining what package your bug might be about at https://wiki.ubuntu.com/Bugs/FindRightPackage. You might also ask for help in the #ubuntu-bugs irc channel on Freenode.

To change the source package that this bug is filed about visit https://bugs.launchpad.net/ubuntu/+bug/1466803/+editstatus and add the package name in the text box next to the word Package.

[This is an automated message. I apologize if it reached you inappropriately; please just reply to this message indicating so.]

[Gareth Evans (garethevans-9)]

added package info

[Gareth Evans (garethevans-9)]

A correction to point 2 in my original report - degraded unencrypted LVM RAID boots but fails to boot when a new virtual disk is atatched (without first declaring the removed one as faulty, to simulate a hardware failure)

To reproduce:

Install Ubuntu Server 14.04.2 in VirtualBox with two 8GB virtual disks - all formats ext4 where required:
Partition each drive:
1GB bootable RAID 10 - md0
7GB RAID 10 - md1

/boot on md0
LVM on md1 (1GB swap, 6GB root)
Finish installation and restart, apply latest updates. Shutdown
Remove one of the virtual drives in VirtualBox
Boot fails

With the encrypted version (RAID 10 > LUKS > LVM) boot fails after installation.

[Gareth Evans (garethevans-9)]

On further testing this report is inaccurate - please ignore it but see #1469269 instead