[vox-tech] SOLVED - Re: Linux live disk's install attempt onto external drive botched my internal drive's grub!

[Brian E. Lavender]

Excellent. Time to resurrect LERT?

On Sat, Jul 16, 2016 at 01:13:08AM -0700, Bill Kendrick wrote:
> 
> Ok, the solution was easy.  From the "grub rescue>" prompt, I had to
> poke around to see what was what, and where.
> 
> My laptop's /boot partition was coming up as "(hd0,msdos1)",
> and when I did an "ls (hd0,msdos1)", I saw things like:
> 
>   grub/
>   memtest86+.bin
>   ...
>   vmlinuz-3.13.0-51-generic
>   initrd.img-3.13.0-51-generic
>   ...
> 
> So all I had to do at that point was tell grub how to boot:
> 
>   set root=(hd0,msdos1)
>   set prefix=(hd0,msdos1)/grub
>   insmod normal
>   insmod linux
>   linux (hd0,msdos1)/vmlinuz-3.13.0-51-generic
>   initrd (hd0,msdos1)/initrd.img-3.13.0-51-generic
>   boot
> 
> A bunch of kernel boot-up noise appeared, and I was prompted to enter
> the passphrase to decrypt my root (/) directory, and after a moment,
> my KDE login screen appeared!
> 
> I brought up a shell, and run "sudo grub-install /dev/sda"
> (notice, not "/dev/sda1").
> 
> Rebooted, and here I am.  Whew!
> 
> Thanks very much to my coworkers (and sometimes LUGOD visitors)
> Case & Dmitriy.
> 
> And also to my wife for putting both kids to bed while I panicked
> in here ;)
> 
> -bill!
> 
> 
> On Sat, Jul 16, 2016 at 12:36:46AM -0700, Bill Kendrick wrote:
> > 
> > So we got a new SSD drive for Melissa's laptop, and I've placed a Kubuntu
> > installer/live demo image onto a USB flash drive.
> > 
> > Melissa was busy working on her laptop, so I decided to just
> > get the install onto the new SSD, and we can physically migrate
> > drives between her laptop at our leisure.
> > 
> > So, I booted _my_ laptop up with the installer USB flash drive, and
> > stuck the target drive for the install (the SSD drive) into an
> > external SATA enclosure, and connected that to my laptop via its USB cable.
> > 
> > Then I told the installer to install onto that external drive.
> > 
> > I answered a few questions, watched the enclosure's blue LED blink at me
> > for 10 minutes while the installer did its job, and done!  "Great," I assume!
> > I unplug the installer USB flash drive, and try to boot up the
> > freshly-installed Linux off of the external drive enclosure.
> > It didn't come up.  That's not good, but not a disaster.
> > 
> > But, it gets worse...
> > 
> > So I unplug the SATA enclosure's USB cable as well, and reboot my laptop again.
> > Now I'm staring at a "grub rescue>" menu!  Nooo! :^(
> > 
> > Apparently, the installer slammed an update to GRUB(?) on my laptop's
> > _internal drive!_  (Full disclosure, I know almost nothing about GRUB since
> > I never need to deal with it.)  So now I can't boot my laptop!
> > (Aaand, since it was handy, and is newer and faster than my personal drive,
> > I was using my work laptop.  "Why should it matter," I assume,
> > "I'm installing Linux onto an _external drive_.")
> > 
> > 
> > I Googled around and discovered something called "boot-repair",
> > which I installed onto the live/install USB flash drive, but when I ran
> > it in it's default / recommended mode, it didn't seem to help me.
> > 
> > The results of its scan can be seen here:
> > http://paste.ubuntu.com/19599532/
> > 
> > It seems like I got bit by this bug...?
> > https://bugs.launchpad.net/ubuntu/+source/grub-installer/+bug/384633
> > 
> > 
> > I'm seeing a LOT of questions and answers about this kind of problem
> > online, but a lot of it is old, a lot of it has to do with people
> > who are trying to boot Linux off an external drive (not my goal;
> > my goal was only to install it there; I guess it was foolish for me
> > to assume that that's a "thing one can do").
> > 
> > I'm asking coworkers for assistance, but since many are remote,
> > I figured I'd ask here, in case someone local feels like dropping by
> > (or meeting me somewhere) to help fix this.
> > 
> > Thanks,
> > 
> > -- 
> > -bill!
> > Sent from my computer
> > _______________________________________________
> > vox-tech mailing list
> > vox-tech at lists.lugod.org
> > http://lists.lugod.org/mailman/listinfo/vox-tech
> 
> -- 
> -bill!
> Sent from my computer
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> vox-tech at lists.lugod.org
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-- 
Brian Lavender
http://www.brie.com/brian/

"There are two ways of constructing a software design. One way is to
make it so simple that there are obviously no deficiencies. And the other
way is to make it so complicated that there are no obvious deficiencies."

Professor C. A. R. Hoare
The 1980 Turing award lecture