Comment 4 for bug 244808

I'm sorry I won't be able to test 11.04 soon.

> - A clear way we can attempt to confirm this behavior (i.e. break an array and then attempt to activate it?)

Most of the issues should be covered by the overview in ReliableRaid and the test cases.
https://wiki.ubuntu.com/ReliableRaid and
http://testcases.qa.ubuntu.com/Install/AlternateRaidMirror with all three partitoning schemes.

ReliableRaid says this about the bug at hand:
Using the legacy method to start degraded raids selectively (mdadm --assemble --run -uuid) will break later --incremental (re)additions by udev/hotplugging. (The initramfs currently uses "mdadm --assemble --scan --run" and starts *all* arrays available degraded! 497186. The corresponding command "mdadm --incremental --scan --run" to start *all remaining* hotplugable raids degraded (something still to execute only manually if at all!) does not start anything. 244808)

> - What you expect the system to do (assemble all inactive arrays?)
By default, it should assemble all raid partitions that are connected with --incremental and run them only when they are complete (as defined by the state of their superblocks) to ensure no arrays are never started partially.

> - What it actually does (??)
On boot, ubuntu starts ALL arrays in degraded mode, if the rootfs is still incomplete after a timeout. It should only start the raids necessary for the rootfs in degraded mode. (how this could be done: see ReliableRaid Wiki)