** Description changed: https://help.ubuntu.com/12.04/serverguide/advanced-installation.html The above page is missing three very important details. 1. /boot must be raid1, since it is apparently the only way to successfully boot degraded. I tested raid10, which boots until you pull any disk, and then you get either a black screen, or: - error: no such disk. - grub rescue> + error: no such disk. + grub rescue> So my solution was to have a separate boot raid device that is raid1, while the root system is raid10. Separate raid10s has the same problem (I had them separated already due to the metadata 0.90 not supporting large disks). - 2. Tt should mention that metadata 0.90 is required on the boot raid device. I am fairly sure the installer did not do this. And from command line I fixed it by backing up the files, destroying and recreating with: - mdadm --create -e 0.90 ... + 2. It should mention that metadata 0.90 is required on the boot raid device. I am fairly sure the installer did not do this. And from command line I fixed it by backing up the files, destroying and recreating with: + mdadm --create -e 0.90 ... 3. With a GPT partition, the installer happily continues without a bios_grub partition, which is very wrong. Manually run, the grub-install command line will produce errors and break the boot, but these don't make it to the installer for the user to see, and the system will still boot until "grub-install" is run. (This is a documentation problem, and also an installer software bug) - My system details: lsb_release -rd Description: Ubuntu 12.04 LTS Release: 12.04 mdadm 3.2.3-2ubuntu1 grub-install - 1.99-21ubuntu3 + 1.99-21ubuntu3 Linux 3.2.0-23-generic
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/997531 Title: doc boot issues: raid10 boot device will not boot when degrade; metadata 0.90 is required; bios_grub is required for GPT To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-docs/+bug/997531/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
