Hi folks, On occasion I boot a live CD and need to have the md RAID devices running. Ordinarily (with Ubuntu live CDs) I find that I need to install the mdadm package after booting the live CD. At that point my recollection is that the RAID devices get started by the scripts that perform the installation (and probably run the startup scripts that are in /etc/init.d/...) Earlier today I did this with a distro that is derived from Debian and under development. I was happy to see that 'mdadm' was already installed. (I had asked for this in fact.) But then I started encountering difficulties. The /proc/mdstat file existed but listed no RAID personalities and none of my devices were started. I tried 'mdadm --assemble -scan' which reported no errors but did not improve the situation. I manually loaded the raid0 and raid1 modules (which caused the personalities to be listed in /prod/mdstat) and pulled in other raid related kernel modules. However 'mdadm --assemble -scan' still did not start my devices. I thrashed around a bit before finding a command that probed drives and listed the md devices and their UUIDs. I was then able to start them using 'mdadm --assemble /dev/md<n> --uuid <UUID>' individually for the RAID devices I wanted to start. I'd like to report back to the person working on this distro the difficulties I had with the RAID and beyond that, I'd like to provide the information that they need to set up RAID so it just works (like on a normal boot) if possible and desirable. First... Are there reasons that other live CDs I've used have not set up RAID? Live CDs by their nature are somewhat lightweight so if adding mdadm uses significant resources perhaps it is best left as a manual operation. Is there something I overlooked in getting it started in this particular situation? Where should I be looking for documentation that would help configuring RAID on a Live CD? I did some searching and the most promising thing I found was https://raid.wiki.kernel.org/articles/r/a/i/RAID_Boot_bac9.html which directs me to a text file in the kernel source tree. (http://lxr.linux.no/#linux+v3.1.1/Documentation/filesystems/ramfs-rootfs-initramfs.txt) And that points to other documentation. I'd appreciate pointers to documentation that is particularly relevant to md RAID form a live CD. many thanks, hank -- '03 BMW F650CS - hers '98 Dakar K12RS - "BABY K" grew up. '93 R100R w/ Velorex 700 (MBD starts...) '95 Miata - "OUR LC" polish visor: apply squashed bugs, rinse, repeat Beautiful Sunny Winfield, Illinois -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
