gpg: Signature made Sun Feb 17 18:04:15 2019 UTC
gpg: using DSA key 2099B64CBF15490B
gpg: Good signature from "Andy Smith <andy@strugglers.net>" [unknown]
gpg: aka "Andrew James Smith <andy@strugglers.net>" [unknown]
gpg: aka "Andy Smith (UKUUG) <andy.smith@ukuug.org>" [unknown]
gpg: aka "Andy Smith (BitFolk Ltd.) <andy@bitfolk.com>" [unknown]
gpg: aka "Andy Smith (Linux User Groups UK) <andy@lug.org.uk>" [unknown]
gpg: aka "Andy Smith (Cernio Technology Cooperative) <andy.smith@cernio.com>" [unknown]
On Sun, Feb 17, 2019 at 05:55:34PM +0000, Andy Smith wrote:
> For those wanting to avoid spoilers, the next email is going to contain
> some comments about what the problem here actually was.
Right, so the situation here was:
- Customer had just done a do-release-upgrade from ubuntu 14.04 to 16.04
and then rebooted.
- VPS did not boot and upon looking at the console it was at a GRuB
screen saying:
*GRUB-legacy from /boot/grub/menu.lst
and then:
Failed to boot both default and fallback entries.
Press any key to continue...
Based on that information I know:
- /boot/grub/grub.cfg (modern grub config file) doesn't exist
- /boot/grub/menu.lst (legacy grub config file) does exist but doesn't
work
These days we generally recommend installing grub-pc package to get the
GRuB bootloader and letting it manage /boot/grub/grub.cfg (paths differ
on CentOS).
So anyway:
- Connect to Xen Shell
- Boot rescue environment
- chroot into actual VPS
- Discover /boot/grub/menu.lst that contains no kernels
- See there actually are kernels in /boot
- Try to update-grub but it isn't installed, implying grub isn't
installed at all
- apt install grub-pc
- set some more sensible options in /etc/default/grub
- update-grub
- exit out of everything and boot the VPS
- Success
Hypothesis: grub-legacy was uninstalled during do-release-upgrade and
never replaced by grub-pc leading to no working bootloader config.
Cheers,
Andy
--
https://bitfolk.com/ -- No-nonsense VPS hosting
