On Thu, Oct 9, 2008 at 12:00 PM, jdd <jdd@dodin.org> wrote:

is it posible to boot from raid (mirror)? I just installed opensuse 11 with software raid and when booting I get "no OS" error.

I have one swap and one partition on each disk (default raid YaST install)

thanks jdd -- http://www.dodin.net http://valerie.dodin.org http://www.youtube.com/watch?v=t-eic8MSSfM -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org

Hi It should be possible to boot from a software raid system. However, I do not know what the bumps along the road would be. I'd solve this problem by creating a 50MB /boot partition on one of the disks and use that to boot. Just be sure to copy the /boot manually to the other disk, in order to be able to boot from both disks. Do not enter this partition in /etc/fstab. If the first disk fails, you'll have a single user login. Use that to enter the new disk in /etc/fstab. Hope it helps Neil -- There are three kinds of people: Those who can count, and those who cannot count ----------------------------------------------------------------------- ** Hi! I'm a signature virus! Copy me into your signature, please! ** ----------------------------------------------------------------------- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org

----- Original Message ----- From: "jdd" <jdd@dodin.org> To: "OS-EN" <opensuse@opensuse.org> Sent: Thursday, October 09, 2008 6:00 AM Subject: [opensuse] booting from raid

is it posible to boot from raid (mirror)? I just installed opensuse 11 with software raid and when booting I get "no OS" error.

Yes. You just have to know more of the details and generally have to take a more active/direct/manual hand in setting it up. There are lots of possible gotcha's, each with one or more work-around. Many have been discussed in detail here many times already. Some of which has ben total garbage guessing or faulty deductions but isn't that the case all the time on any topic? Basically you can't just expect yast to do it right. You have to know exactly what all is going on and create the working config yourself, from bios settings to grub config to os config. At minumum, /boot must be on a plain partition, which may be a member of a raid1, no other options possible for /boot. Everything else can be anything you want. You may have other problems beyond this, but "no os" means your motherboard found nothing at the spot where it tried to load a boot loader from. opensuse by default wants to put a generic minimalist bootloader in an mbr somewhere (maybe it doesn't choose the right disk) and that bootloader is very simple and only knows how to load some other bootloader from some partition. That is a good idea for several reasons, but I personally have less than good success with it and I always force grub to install directly to the mbr, and for software raid, I go further and force it to install to the mbr of every disk in the array, and /boot is always a raid1 where there is an identical copy of /boot on every disk in the array. So, every disk can be booted, so it doesn't mater if the bios picks a different one as the first disk than what grub or the linux kernel would pick, and doesn't matter if the 1st disk happens to be the one that dies. That is not "the right way". And so I am not telling you to do that. It's merely one way, and perhaps not the simplest or most practical or least error prone or least delicate. It's just what I happen to do. It does require me to do almost every part of the config manually. The trade off is, per force, I know all the gory details about how my boxes boot, and so when there is a problem, generally I can handle it instead of being left staring at a broken box helplessly. My suggestion is you should do the same if you are going to use software raid. Experiment with grub manually until you know all the ins & outs. Only after that actually run your system that way. Unless that's exactly what you're doing right now and this is just a test box. In that case we just need more details before it's possible to help. There are only about 50 ways that you could end up with "no os". We have nothing to go on here to guess which of them might be your problem, or if you found a 51st way for that matter! heh. :) All we know right now is, the motherboard bios went somewhere to get a bootloader and didn't find one. So First is, identify where did the bios look? Or, go into bios setup and force it to look someplace specific from now on. Next is somehow (and there are countless ways) place a bootloader there. Next is configure that bootloader so it knows how to load a kernel and initrd. Next is configure that kernel and initrd so that once loaded it knows how to mount your fs's. Breaking the problem down makes it less of a mystery. Each of these steps needs a lot more expansion, but you can probably do the first at least already, just by having it expressed that way. -- Brian K. White brian@aljex.com http://www.myspace.com/KEYofR +++++[>+++[>+++++>+++++++<<-]<-]>>+.>.+++++.+++++++.-.[>+<---]>++. filePro BBx Linux SCO FreeBSD #callahans Satriani Filk! -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org