On Tue, Jun 25, 2013 at 5:51 PM, Mark Knecht <markkne...@gmail.com> wrote: > This is related to my thread from a few days ago about the > disappointing speed of my RAID6 root partition. The goal here is to > get the machine booting from an SSD so that I can free up my five hard > drives to play with. > > SHORT SUMMATION: I've tried noninitrd and noraid in the kernel line of > grub.conf but I keep booting from old RAID instead of the new SSD. > What am I doing wrong?
Here are some things I would try to narrow it down: Put raid=noautodetect on your kernel commandline to prevent the kernel from auto-assembling the array It sounds like you are pretty sure it is at least using the boot sector of the new drive, so I am thinking it is possible there is some weird combination of using a boot sector from one drive to get you into the boot partition of another drive. If the old boot drive is still attached, you could try moving/renaming the grub config or whole grub folder on the old boot drive to make sure it's not getting used. If that doesn't give any clues, I would physically unplug the cable of every drive other than the SSD (if that is realistic based on your filesystem layout) and see how far it gets. Maybe if it fails you can figure out what it's trying to access on the other disks. As far as the RAID I think there are at least a few different ways an mdraid array comes to be assembled: - your initramfs does it - your kernel does it (only for a RAID with v0.90 superblock) - init script does it (/etc/init.d/mdraid) - udev does it (/lib64/udev/rules.d/64-md-raid.rules) - you manually do it later on using mdadm Viewing dmesg output from around the point where boot begins and the RAID is assembled might give you some clues about who's doing what. I recently upgraded my machine and disks and am using UUID and labels for everything, I can literally boot from either the old HDD or new HDD from my BIOS boot menu, plugging them into the motherboard in any order, and either one will work properly, even though the /dev/sdX assignments might change from boot to boot. You can use the blkid command (as root) to see the labels and UUIDs for all of your drives and partitions. Good luck, Paul
