** Description changed: + Ubuntu still uses the kernel option + CONFIG_MD_AUTODETECT=y + thus enables the kernel's RAID autodetection during boot. - Ubuntu's current kernel option - CONFIG_MD_AUTODETECT=y - enables the kernel's RAID autodetection during boot. - - Aside from causing a delay for everyone this often also disturbs the udev/mdadm setup of raid devices in the system. - (i.e. devices partly busy/set up without an entry in the mapfile used by mdadm --incremental) + However, aside from causing a delay for everyone, this often also disturbs the udev/mdadm setup when raid devices are present in the system. + (i.e. devices are partly busy/set up by the kernel, without an entry in the mapfile used by mdadm --incremental) Here is what README.initrams from mdadm tarball says about the kernel's - raid autodetection feature: + raid autodetection features: "while useful, [they] do not provide complete functionality and are unlikely to be extended. The preferred way to assemble md arrays at boot time is using 'mdadm' " - Ubuntu does this using udev rules in initramfs as well as later on. + Ubuntu does assemble arrays using udev rules that run mdadm. (In + initramfs as well as later on.) - The kernel's raid autodetection should therefore be disabled in ubuntu - kernels. + The kernel's raid autodetection can and should therefore be disabled in + ubuntu kernels.
-- enabled kernel raid autodetection disturbs udev/mdadm (initramfs & later) https://bugs.launchpad.net/bugs/551719 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
