In order to support updating anaconda to create mdadm raid arrays that use version 1.0 or later superblocks, we have to quit use raid autorun from the kernel. The kernel does not support autorun on raid arrays with a superblock version of 1 or higher. Anaconda already writes out the information needed to uniquely identify each array by UUID to /etc/mdadm.conf at startup, so the following changes should be sufficient: any time we have $raiddevices to start, install mdadm.static as mdadm and /etc/mdadm.conf as itself on the initrd image, then when we loop through the $raiddevices list, instead of creating nodes and calling raid autorun, create the node then call mdadm -A --scan /dev/$dev in the rc.linux script. The attached patch implements this behavior.
Created attachment 140076 [details] mkinitrd patch to fix issue - tested and working
I'd suggest adding --run and --auto-update-homehost to the mdadm command line, such that it will start degraded arrays (wouldn't it suck to be completely unable to boot because your / went degraded?) and to enable other failure-recovery scenarios after bringing disks from other machines.
--auto-update-homehost defeats the purpose of having a homehost in the first place when on a NAS/SAN. You need to be required to do that manually, especially since you should never be changing the home host of your boot or / partitions unless you change them together. If you do want to change them separately, then rescue mode on the CD is fine. However, the --run parameter is perfectly fine. I will note that this bug has been languishing, and I'm pretty sure that the combination of this and the total lack of a few sanity rules in the anaconda installer has resulted in bug 230860. If at all possible, this needs fixed prior to F7 going gold. I'll open a separate bug (or two) against anaconda. Note: without fixing this, it's possible for users to create an installation that is guaranteed to never run their raid arrays properly at bootup. Raid autorun is dying, and will be totally dead in the future. This is needed to start raid arrays without raid autorun.
Created attachment 154438 [details] mkinitrd-6.0.9-mdadm.patch Okay, this is an updated version of the previous patch which adds the --run flag and applies cleanly against mkinitrd-6.0.9. As I understand it, if we don't apply this patch, anyone with mdraid who upgrades from FC6 may have serious trouble on first boot. Peter, can you please look this over and consider adding it?
Possible dups: bug #238926, bug #238353
Okay, we've got patched packages built in koji. Doug, do you have some way to test these out and see if they Do The Right Thing? http://koji.fedoraproject.org/koji/buildinfo?buildID=6450 has the updated mkinitrd packages.
Verified with local version of -5 that I'm building now
Changes are verified from my end.