Comment 5 for bug 136252

After the update to 9.04 I had the same problems but could build the md devices in the emergency shell and resumed booting with:

# mdadm --assemble --scan;exit

Today I found the fix. I removed the duplicated definitions of the arrays in mdadm.conf with the output of:

# mdadm --detail --scan

this added the information for the metadata - 0.90 if you are wondering

The other change that I made was editing the DEVICE line from:

DEVICE partitions

to:

DEVICE /dev/sda[1-4] /dev/sdb[1-4]

The last step was to rebuild the initrd with the new config file.

# update-initramfs

after that the system of my grandparents is booting again without the need of them entering a cryptic line on every start up.

Some questions that still remain:

1. Why does the RAID brake on every ubuntu version upgrade since about 3 years?
2. Why the mdadm.conf contained duplicated array and device lines?
3. Why can't mdadm report a broken configuration in a way so that I don't need a week or two too fix the problem?

Regards, Dominik