grub contains too few modules in rescue mode

[Hiram]

Binary package hint: grub2

I installed Karmic Koala alpha 2 in vmware on a real partition on my macbook 5.1. When i tried to boot karmic nativly instead of in vmware fusion, grub2 failed saying 'error: no such partition'. The resulting rescue commandline however contained not enough commands to actualy be able to rescue me.

it listed 'help' as an command to view the available command but help was not available.

i found only the following commands present:
ls, set and uset

I would advise to atleast include help and halt.

however i kind of expect root, insmod, lsmod, rmmod, cat also to be present.

[Felix Zielcke (fzielcke)]

insmod is always avaible in rescue mode. If not then it's a bug.
root isn't needed, you can use set root= just like in grub.cfg.
The other commands you mentioned are now in minicmd.mod so if you or Ubuntu in general wants to have that avaible in rescue mode you need to include it in the grub-mkimage line in grub-install, but that increases core.img about 4 KiB.
I don't think we'll change this again upstream (GNU and Debian).

[Hiram (hiram-)]

my bad, insmod is included as you said.

I agree that most of this should not be included in the core.img.
however at least for ubuntu help should be included. because its an enormous usabilty issue if you hint for help and it isnt there. And I would expect some command to shutdown (I assumed halt does such a thing) since it is not always possible to kill the power etc. Also for people who don't dare to powe cycle and just wan't to shutdown and call someone technical.

Maybe i just expect to much from the grub rescue prompt when it cannot find its devices. So your probably right about the other commands.

[Michael Helmling (supermihi)]

I totally agree with hiram and add a screenshot to demonstrate my frustration. ;-) This does NOT fulfill ubuntu's usability demand!

[Colin Watson (cjwatson)]

The main problem here is that increasing the size of rescue mode would make it impossible to embed GRUB's core.img in the 32KB region immediately following the MBR on PC systems, which would make it much less reliable. We're already very close to the boundary.

'insmod help' should load help; perhaps it would be sufficient to recommend that.

[Colin Watson (cjwatson)]

Though of course if rescue mode can't find enough devices to load normal mode then insmod may not work either ...

[Marcus Tomlinson (marcustomlinson)]

This release of Ubuntu is no longer receiving maintenance updates. If this is still an issue on a maintained version of Ubuntu please let us know.

[Launchpad Janitor (janitor)]

[Expired for grub2 (Ubuntu) because there has been no activity for 60 days.]