GNU GRUB: Difference between revisions

From NixOS Wiki
imported>Fadenb
Adds: How do I use GRUB in text mode?
imported>Fadenb
fix grub textmode instructions
Line 15: Line 15:


=== How do I use GRUB in text mode? ===
=== How do I use GRUB in text mode? ===
Sometimes you need to access GRUB in text mode (e.g. when using out of band management systems like HP ILO in "textcons" mode).


Sometimes you need to access GRUB in text mode (e.g. when using out of band management systems like HP ILO in "textcons" mode). To enable text mode you have to disable the GRUB splash screen:
To use GRUB in text mode there are two settings that need to be configured depending on whether you use EFI or BIOS boot:


<syntaxhighlight lang="nix">
<syntaxhighlight lang="nix">
boot.loader.grub.splashImage = null;
boot.loader.grub.gfxmodeEfi= "text";
boot.loader.grub.gfxmodeBios= "text";
</syntaxhighlight>
</syntaxhighlight>
Only disabling the GRUB splash screen via <syntaxhighlight lang="nix" inline>boot.loader.grub.splashScreen = null;</syntaxhighlight> results in a similar output but that is not the real text only mode.

Revision as of 13:13, 1 January 2018

FAQ

How do I remove older generations from the bootloader?

First, collect garbages in your system, then rebuild. The scripts will collect leftover files.

The first command, in the example below, removes everything older than 14 days.

 $ sudo nix-collect-garbage --delete-older-than 14d 
 $ sudo nixos-rebuild boot

How do I use GRUB in text mode?

Sometimes you need to access GRUB in text mode (e.g. when using out of band management systems like HP ILO in "textcons" mode).

To use GRUB in text mode there are two settings that need to be configured depending on whether you use EFI or BIOS boot:

boot.loader.grub.gfxmodeEfi= "text";
boot.loader.grub.gfxmodeBios= "text";

Only disabling the GRUB splash screen via boot.loader.grub.splashScreen = null; results in a similar output but that is not the real text only mode.