Hi Philip. Thank you so much for taking time to answer me, I feel less alone now :)
2007/12/4, Phillip Susi <[EMAIL PROTECTED]>: > ben.div wrote: > > Woh ! Absolutely nobody can help me on this question ? I've already > > asked about this on 4-5 lists or forums, and I've cumulated : 0 answer. > > Where could I find help on this subject ? The kernel team ? Who has > > developped this part (boot on initramfs and device detection) ? > > > > I'm stucked on that problem since 2 weeks. Please, help :) > > Known issue... though I can't seem to find the bug # now. > What is a known issue ? Running a degraded raid 5 at boot is not possible ? > > Ben Ben a écrit : > >> So here, I suspected that the wrong option was passed to mdadm in > >> initramfs, and tell it to not to run a degraded array. > >> I've found (with grep on initrams content) that the file > >> /etc/udev/rules.d/85-mdadm.rules contains this line : > >> > >> SUBSYSTEM=="block", ACTION=="add|change", ENV{ID_FS_TYPE}=="linux_raid*", \ > >> RUN+="watershed /sbin/mdadm --assemble --scan --no-degraded" > >> > >> I guess it's the boot parameter for mdadm ! So, I changed it, made a new > >> initramfs, reboot with only 2 disks and... nothing more, it doesn't > >> start anymore :/ > > Not sure what's going wrong without any description other than "it > doesn't start anymore", but that should allow you to boot in a degraded > array. > It does the same thing I describe before : initramfs loads, md driver try to run array but can't, so it hangs around 3 minutes and give me the hand in the initramfs console. Here's outputs of cat /proc/mdstat at this stade. I gave many try (reboot), as the output is not always the same : $ cat /proc/mdstat Personalities : [raid0] [raid6] [raid5] [raid4] [linear] [multipath] [raid1] [raid10] md1 : active raid0 sda5[0] sdb5[1] 78164032 blocks 64k chunks md0 : inactive hda3[0] 116141824 blocks unused devices: <none> $ cat /proc/mdstat # with kernel 2.6.22.14 md drivers compiled inside kernel (not as module) Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4] [multipath] [faulty] md1 : inactive sdb5[1] 39102080 blocks md0 : inactive hda3[0] 116141824 blocks unused devices: <none> $ cat /proc/mdstat Personalities : [raid0] [raid6] [raid5] [raid4] [linear] [multipath] [raid1] [raid10] md1 : active raid0 sda5[0] sdb5[1] 78164032 blocks 64k chunks md0 : inactive hda3[0] 116141824 blocks unused devices: <none> $ cat /proc/mdstat Personalities : [raid0] [raid6] [raid5] [raid4] [linear] [multipath] [raid1] [raid10] md1 : inactive sdb5[1] 39102080 blocks md0 : inactive hda3[0] 116141824 blocks unused devices: <none> All these test have been done with all 3 disks up, and with --run option for mdadm in /etc/udev/rules.d/85-mdadm.rules. You can see that md0 is never ran, and md1 (raid0) is sometime ran, sometimes not. Here, if I stop and launch manually the md, it works. If I give the option --no-degraded to mdadm, it work always (if the array is not degraded). > >> So, after this long story (sorry), my questions : > >> > >> Do you think I'm totally lost, or editing this file is the good way ? > >> Is there a good reason why ubuntu's dev chose this "--no-degraded" > >> option for mdadm by default ? > >> What can I do more ?? > > The reason is because we don't want to degrade an array just because one > of the disks has not been detected yet. The proper solution is to wait > for either a timeout or manual intervention to go ahead and mount the > array degraded. > Why does the --run option never work, but --no-degraded work, even if the raid array is not degraded ? It seems like you suggest to be a "disk not detected yet" problem. How could I workaround this ? Maybe a "sleep 10" before launching mdadm ? But why are the disk detected for md1 (raid1), but not for md0 (raid0), while it use the same devices (sda, sdb for md1, hda, sda, sdb for md0) ? Maybe it's a udev syntax problem (I didn't take time to study it) ? Another question : you said I can run the array manually and launch back the boot process. How can I do this last point ? running /init ? Thank you ! Ben -- Ubuntu-devel-discuss mailing list Ubuntu-devel-discuss@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-devel-discuss