Bug#989124: grub-installer: occasional failure to install grub (when two DEs selected)

[Philip Hands <phil@hands.com>]

Package: grub-installer
Version: 1.178
Severity: minor

Dear Maintainer,

While testing under openQA (so in qemu/kvm) if selecting more than one DE,
somthing like one in ten installs will fail to install grub, resulting in an
unbootable system.

Given that this is only happening in the unusual circumstance of selecting
multiple desktops, and even then is only an intermitent bug, I've tagged it as
minor.

An example of this can be found here:

  https://openqa.debian.net/tests/4457

which one can see hanging at the initial boot screen, rather than booting to a login prompt.

One of the assets being collected it a dump of the start of the target block
device, which in the failing case looks like this:

  https://openqa.debian.net/tests/4457/file/complete_install-dev_vda_dump.txt

whereas when things are working it looks like this:

  https://openqa.debian.net/tests/4439/file/complete_install-dev_vda_dump.txt

I have tried making it collect data earlier during the install
but doing so resulted in bug going away.

[I had it flip to the console when mandb is being installed, as that sits on the
screen for quite a while so provides a good trigger for the action, and run a
few commands to collect state, then flip back to the graphical screen.]

BTW The syslog from that failing run is here:

  https://openqa.debian.net/tests/4457/file/complete_install-syslog.txt

If there's more information that could usefully be collected, please mention
what you think might help and I'll add it to the openqa scripts.

Cheers, Phil.