Running "grub-install /dev/sda" in a live environment "fixes" the machine so
it will boot.

Unless there's a good reason not to though, I'd like to know why the current
method doesn't work, and find a general solution that will work for any
setup.  See my last email.

And also, I can't seem to find "grubby".  It's not included on the fedora
rescue cd or ubuntu live cd, and the fedora live cd keeps giving me a kernel
panic when I try to boot it.  But that's a separate issue for now.
-Andrew

On Wed, Aug 20, 2008 at 2:25 PM, Andrew Brown <[EMAIL PROTECTED]> wrote:

> On Wed, Aug 20, 2008 at 7:44 AM, Michael DeHaan <[EMAIL PROTECTED]>wrote:
>
>> Andrew Brown wrote:
>> > On Tue, Aug 19, 2008 at 6:16 PM, Michael DeHaan <[EMAIL PROTECTED]
>> > <mailto:[EMAIL PROTECTED]>> wrote:
>> >
>> >     Andrew Brown wrote:
>> >     > Okay, a few things since yesterday:
>> >     > I'm not worrying about the hard drive device issue for the
>> >     moment, it
>> >     > seems to be related to whether the bladecenter media tray is
>> >     assigned
>> >     > to that blade or not.
>> >     >
>> >     > I've also edited the code to ignore listed partitions of type
>> >     "Empty"
>> >     > or "Extended"
>> >
>> >     Is there a new attachment we can look at for this?
>> >
>> >
>> > I've attached the most recent base.cfg which contains the code.  Keep
>> > in mind that today I did things manually though, not using the script.
>>
>>
>> >
>> >
>> >
>> >     >
>> >     > But somehow the process isn't working.  I followed the process
>> very
>> >     > closely of xcat, a similar provisioning engine.  After taking and
>> >     > restoring an image, it doesn't boot.
>> >     >
>> >     >
>> >     > I tried the process manually today.  That is, I booted with a
>> >     live cd
>> >     > and ran each command myself.  Saved the mbr, saved the partition
>> >     table
>> >     > with sfdisk, and saved the contents of each partition of a freshly
>> >     > installed linux installation.
>> >     >
>> >     > Then I went to the next blade, identical hardware and setup, and
>> >     > booted the live cd up.
>> >     > -Restored partition entries with sfdisk
>> >     > -Restored mbr with dd
>> >     > -Restored partitions again with sfdisk.  I don't fully
>> >     understand why
>> >     > it's done again,  this was just following the xcat process (for
>> >     which
>> >     > I can post the exact code if anyone's curious).
>> >     > -And of course restore all partitions one at a time
>> >     >
>> >     > When I tried to boot it back up, it got as far as printing
>> >     "GRUB" and
>> >     > hung there.  I need some help here, I'm not sure what's going on.
>> >
>> >     One thing to check is to stop before rebooting and see if grub is
>> >     installed correctly, or if any errors happen during grub-install.
>> >       For
>> >     that, it may be worth running through the script line by line or at
>> >     least logging the output of each step w/ debug output printed before
>> >     each command as needed.
>> >
>> >
>> > Like I said, I did the entire procedure manually... entered each
>> > command myself so I knew exactly what was running.  Once I get it
>> > working manually, I can easily find out if my script is doing things
>> > any differently.
>> >
>> > How do I tell if grub is installed correctly?
>>
>> "grubby" has some probe options that should do this.   See "man grubby"?
>>
>> >
>> >
>> >
>> >
>> >     >
>> >     > I tried a different order to restoring partition/mbr info: Restore
>> >     > partition stuff with sfdisk, and then the mbr with dd.  I was
>> >     thinking
>> >     > sfdisk may have overwritten the mbr or something, but I got the
>> same
>> >     > results.
>> >
>> >     Grub lives in the MBR, though are you calling grub-install after
>> >     all of
>> >     that?
>> >
>> >
>> > Right.  I'm not calling grub-install.  I didn't think it was
>> > necessary.  Grub lives in the mbr, which is the first 512 bytes of the
>> > drive.  I'm saving the mbr to a file and restoring it back.  Shouldn't
>> > that be sufficient?
>>
>> In theory, assuming it's not a GPT partition /and/ grub lives in the MBR
>> (both of which can't really be assumed), yes.
>>
>> It's best to use grubby, the command line tool, for manipulating
>> grub.    As a bonus it also knows how to manipulate lilo and elilo.
>> There is some code in koan that references a few common grubby commands,
>> though you'll probably want to change this around.
>>
>> --bad-image-ok does not work, but otherwise what you see koan using for
>> the live CD is close.
>>
>> Also there are some bits of the live config script that are using
>> grub-install.
>
>
> So I suppose I'm wrong in assuming that saving the mbr+partition layout and
> each partitions' contents, and then restoring each component is not
> sufficient for perfectly duplicating a hard drive.  Where else could data
> lie?
>
> I'll look into using grubby to make sure grub is installed, but I still
> don't know why this doesn't work as is, things should be restored exactly as
> they were, right?
>
> And further, what about systems that don't use grub, such as windows?  How
> are we going to do this so that it's still cross platform?
>
> -Andrew
>
>
>>
>>
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