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Re: [LUG] The disc drive for / is not ready yet or not present

 

On 02/09/12 21:16, bad apple wrote:
>
> For future reference, you fix these issues by netbooting an appropriate
> installer image (or you can boot via USB or DVD of course, but
> netbooting is easier and more efficient) and breaking into a root shell.
> 
> Issue bind mount instructions for the special filesystems, mount your
> old root and then chroot into the damaged system (there are tutorials
> all over the net for this, such as
> http://karuppuswamy.com/wordpress/2010/06/02/how-to-chroot-to-ubuntu-using-live-cd-to-fix-grub-rescue-prompt/).
> Now you have full access to your old system but from a basis of a
> current, fresh installer environment so you will have working
> networking, etc.
> 
> Then you can fix any damage - for interrupted upgrades, on Debian-based
> systems, the laundry list of apt/dpkg commands Tom posted is pretty much
> everything you'll need. Once you've finished, unmount, exit your shells
> and reboot into your repaired system. This method can be used for any
> linux system, not just ubuntu, although minor details will change
> between distributions.

Yes, I think it worth saying that if you can mount your file systems and
the contents of those are not corrupt, then the system is usually easily
salvageable.

Although in the case mentioned of a half completed upgrade it can be
painful, depending what the reason for the upgrade not completing
properly was.

I hit a problem with upgrading to Debian Testing a few weeks back, where
the resolution was fiddly and I suspect most folk would have been best
advised to reinstall. I would have reinstalled except I didn't want the
down time since the machine was mostly working despite being stuck
mid-upgrade.

I'd do reinstalls over upgrades all the time, if only I was disciplined
enough to keep all the config changes under revision control so I know I
can reimplement ALL of them.


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