update-initramfs fails to manage a RAID array declaration in mdadm.conf

[Eric_DL]

I configured an md RAID1 array to host users' data (intent is to mount formatted RAID volume at /home at boot).
I first simply rebooted the machine to see if array was starting, and it was, but was always getting a /dev/md127 pointer instead of the /dev/md0 I had configured.

So, I searched the web and found that I had to save array configuration in /etc/mdadm/mdadm.conf.
Rebooted again and still, array would start with a /dev/md127 pointer.

I then ran update-initramfs but got the following warning :

W: mdadm: the array /dev/md/mrblack:0 with UUID 8dec57a9:f62b8cd2:bc2d6172:cc0df127
W: mdadm: is currently active, but it is not listed in mdadm.conf. if
W: mdadm: it is needed for boot, then YOUR SYSTEM IS NOW UNBOOTABLE!
W: mdadm: please inspect the output of /usr/share/mdadm/mkconf, compare
W: mdadm: it to /etc/mdadm/mdadm.conf, and make the necessary changes.

After many modification attempts on mdadm.conf, I realized that update-initramfs would actually only consider an ARRAY line in that file, if it exposed an array's UUID, and only with the keyword UUID in upper case (while mdadm.conf's man page shows only the main keywords like DEVICE, ARRAY, HOMEHOST, .... in upper case).

Anyway, I was happy I had finally got rid of the warning, but it didn't help : this time, array would not start at all at boot ! .... although a simple "sudo mdadm -As" would manually start the array without problem afterwards.

All in all, the only configuration that paradoxically worked was commenting all devices and array declarations in mdadm.conf (as you can see in mdadm.conf file attached), until update-initramfs said :

W: mdadm: /etc/mdadm/mdadm.conf defines no arrays.

Now, at boot, mdadm scans for all devices, gets information only from the superblocks and starts the array correctly.

My guess is both initramfs-tools and mdadm have problems at managing mdadm.conf file correctly, or at least there are incompatibilities between each other's way of doing things => I'll affect the report to both.

ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: initramfs-tools 0.103ubuntu0.2.2
ProcVersionSignature: Ubuntu 3.5.0-48.49-lowlatency 3.5.7.31
Uname: Linux 3.5.0-48-lowlatency x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.6.1-0ubuntu13
Architecture: amd64
Date: Mon Jun 9 23:57:20 2014
InstallationDate: Installed on 2013-05-26 (379 days ago)
InstallationMedia: Ubuntu-Studio 12.10 "Quantal Quetzal" - Release amd64 (20121017.1)
MarkForUpload: True
PackageArchitecture: all
SourcePackage: initramfs-tools
UpgradeStatus: No upgrade log present (probably fresh install)