GRUB does not display the menu after changing GRUB_TIMEOUT: causes and definitive solution

When you change the value of GRUB_TIMEOUT but the menu of Boot doesn't appear, the feeling is that you're adjusting something that the system ignores. In practice, there's usually another option that controls more than There waiting and therefore the menu remains hidden even if you have modified the configuration file correctly. The key is to understand how GRUB_TIMEOUT and GRUB_TIMEOUT_STYLE interact., and in applying changes safely.

In this article you will find a clear and in-depth explanation to resolve the typical case of “the GRUB menu does not appear when changing GRUB_TIMEOUT”. We will review the /etc/default/grub file, we'll discuss legacy variables that can still get in the way, go over special timeout values, and you'll also see a graphical alternative with Grub Customizer if you'd rather not touch the console. We've also included diagnostic solutions in case the problem persists on computers with graphics Intel or other specific scenarios.

Why doesn't the GRUB menu appear even if I change GRUB_TIMEOUT?

The first thing is to understand that GRUB_TIMEOUT does not decide on its own whether the menu is displayed. The visibility of the menu is mainly controlled by GRUB_TIMEOUT_STYLE, which can be configured as hidden (hidden) or menu (show menu). If you are in hidden, time passes “in the shadows” and, therefore, you do not see the list of systems or cores. Setting GRUB_TIMEOUT=10 will not make the menu appear si GRUB_TIMEOUT_STYLE remains hidden.

In modern systems, the relevant setting is in /etc/default/grub. If you want to see the menu, make sure that Grub_timaout_style = menu. This is especially useful if you need change boot order in dual-boot configurations. Otherwise, even if you set a generous time, the user won't see anything on the screen. This setting is the one most overlooked when you change only GRUB_TIMEOUT and you notice no effect.

It is worth remembering the special values de GRUB_TIMEOUT: if you put 0, the system boots immediately without showing the menu at all; if you put -1, the charger will wait indefinitely to choose an entry. In addition, in many distributions the value GRUB_TIMEOUT=5 is the default, meaning that if the menu is displayed, the default option will be selected after five seconds of inactivity. Choosing the right value It depends on whether you want interaction or auto-start.

On single-OS machines, some distributions configure the boot so that the menu is not displayed by default. This is intentional to simplify the experience for newcomers, but advanced users prefer to see the menu to choose older kernels or access advanced options. In these cases, putting GRUB_TIMEOUT_STYLE=menu or with a GRUB_TIMEOUT greater than zero is usually sufficient. If you still don't see anything, review the inherited variables we discussed below.

Historically, some configurations included GRUB_HIDDEN_TIMEOUT y GRUB_HIDDEN_TIMEOUT_QUIET. These lines can hide the menu silently and cancel your intention to show it with GRUB_TIMEOUT. If you find them, the most practical thing is to comment on them by prefacing them with the character # so that they do not apply. This way you avoid conflicts with modern GRUB logic; if you reach a critical point you may also be interested in how fix GRUB rescue when the charger does not start.

Finally, do not forget that after any change in /etc/default/grub you must regenerate the configuration running sudo update-grub. This command recreates the effective configuration file from your preferences. If you skip this step, you won't see any effect upon restart, even if you've edited everything correctly; it's also good to know practical examples of efibootmgr if you work with UEFI entries.

Quick checks of the /etc/default/grub file

Open the configuration file with your favorite editor and administrator privileges. On GNOME systems, you can use gnome-text-editor o gedit, and of course you can also opt for nano or vim. A couple of convenient examples would be: sudo gnome-text-editor /etc/default/grub o sudo gedit / etc / default / grub, depending on what you have installed.

sudo gnome-text-editor /etc/default/grub
# o bien
sudo gedit /etc/default/grub

Once opened, look for the line GRUB_TIMEOUT_STYLE. If it is like hidden, change it to menu. Then check the time and the special value you set. An example of a functional block could be the following:

GRUB_TIMEOUT_STYLE=menu
GRUB_TIMEOUT=10
GRUB_DEFAULT=0
#GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true
GRUB_CMDLINE_LINUX_DEFAULT='quiet splash'
GRUB_CMDLINE_LINUX=''

Note that the lines GRUB_HIDDEN_TIMEOUT y GRUB_HIDDEN_TIMEOUT_QUIET can force silent behavior. If you want to make sure you see the menu, leave the first one commented out as in the example. Also, if you wish, change GRUB_TIMEOUT a -1 will allow the menu to remain on hold indefinitely. Useful for laboratory equipment or to diagnose complex startups.

Save the changes and run the GRUB rebuild. Without this step, as we mentioned, the system will continue using the previous configuration, and your edit will appear to be useless. The key command is

sudo update-grub

When finished, reboot to validate. On many computers, you can force the menu to appear during boot by holding down the key. Shift in systems with BIOS inherited or the key I on computers with UEFI, which is very practical for testing. If after this it does not appear, continue with the troubleshooting section; and if you are working with UEFI firmware, you can check out how use the UEFI shell for advanced diagnostics.

GRUB2 vs GRUB Legacy: Where to Change the Timeout

The vast majority of current distributions use GRUB2, but there are still old systems with GRUB Legacy. Knowing which version you have is very simple: go to /boot/grub and see if it appears grub.cfg (GRUB2) or, instead, menu.lst (Legacy). This detail determines the file and configuration keys you need to modify.

In GRUB2, as we have seen, preferences live in /etc/default/grub, and the correct flow is edit, save, and then run sudo update-grub for the file to be regenerated grub.cfg. This process is the recommended one by GRUB documentation and by most Debian and Ubuntu based distributions.

If, however, your system uses GRUB Legacy, the timeout is in the file menu.lst. You would just have to edit it as administrator with a graphical or terminal and adjust the directive timeout. An example of a typical line would:

timeout 10

Save and restart to apply the change. Although this scenario is becoming less common, it's helpful to recognize it to avoid confusion. If you are not sure, check for the presence of the mentioned files and act accordingly to avoid editing wrong locations; in some cases it may be necessary restore the original Windows bootloader if the previous installation installed another manager.

Activate and adjust the menu with Grub Customizer (graphical interface)

If you prefer to avoid the console, you have at your disposal Grub Customizer, a graphical tool that makes managing the boot menu in GRUB2 and Burg easier. With it, you can show or hide the menu, change the order of entries, modify the default option, adjust the wait time, and even customize colors and background images. It is very practical when you're looking for comfort and visual control.

On Ubuntu and derivatives (such as Linux Mint), you can install it from its official PPA. The commands to execute are simple and you can enter them one after the other in a terminal. Be sure to check the packages that are installed and confirmed when the system requests it.

sudo add-apt-repository ppa:danielrichter2007/grub-customizer
sudo apt update
sudo apt install grub-customizer

After installing, open it from the applications menu. You'll find three main tabs: List settings, General configuration y Appearance settingsIn the General tab, you can select menu visibility and adjust the wait time. Don't forget to press Save to apply the changes, and reload the configuration when the tool suggests it.

In the list tab, you can rename, delete, or reorder entries with a right-click, and change the font, colors, or background. There's also a section for Advanced configuration which exposes values ​​such as GRUB_DEFAULT, GRUB_TIMEOUT o GRUB_MENU_PICTURE. Handle with caution if you are not familiar with each parameter.

Common problems and effective solutions

If you have adjusted GRUB_TIMEOUT_STYLE y GRUB_TIMEOUT and yet the menu still doesn't appear, think of causes related to graphics or video mode. On some computers with Intel HD Graphics, add the kernel parameter i915.modeset=1 has helped resolve display issues during boot. The idea is to stabilize the graphic mode which uses GRUB and the kernel at early boot.

To test it, edit /etc/default/grub and add that parameter in GRUB_CMDLINE_LINUX_DEFAULT along with others you already have (for example, quiet splash). In addition, it is advisable to return GRUB_GFXMODE a auto if you had him forced into a specific resolution. An example how it would look:

GRUB_CMDLINE_LINUX_DEFAULT='i915.modeset=1 quiet splash'
GRUB_GFXMODE=auto

Save, run sudo update-grub and reboot to check if the menu is now displayed correctly. If you don't notice improvement, removes the parameter i915.modeset to leave it as it was and regenerate GRUB again. On Manjaro-based systems, some users prefer to reinstall the card drivers with the utility mhwd After tweaking GRUB, using a command like sudo mhwd -a pci free 0300. This step is specific of that ecosystem and does not apply to all distributions. It is also worth reviewing problems arising from Secure Boot and UEFI which may prevent unsigned loaders from running correctly.

Another typical source of confusion is forgetting that, with GRUB_TIMEOUT=0, even with the style in menu, the boot will be immediate and you won't see anything. Raise that value 5, 10, or 15 seconds (depending on your preference) to give yourself room to maneuver. And if you're diagnosing a specific problem, GRUB_TIMEOUT=-1 It may be convenient for you because forces indefinite waiting until you choose.

If you have multiple kernels installed, remember that in the “Advanced Options” section of the GRUB menu, you can choose an older kernel if the last one is giving you problems with a driver or module. Many distributions retain multiple kernels precisely for these cases. For example, if something went wrong with a newer kernel, you can boot with the previous one until you apply a fix or reinstall a driver. It's a great lifeline when a recent change breaks something.

Finally, avoid hot-touching production equipment: the ideal is test changes on a virtual machine or in a controlled environment, verify that you get the desired behavior, and then take it back to your core team. A small syntax error in the file can complicate the start-up if you don't detect it in time.

GRUB_TIMEOUT values ​​and their actual effect

To recap precisely: GRUB_TIMEOUT = 0 causes instant boot without displaying the menu; GRUB_TIMEOUT=-1 keeps the menu on screen indefinitely; and any positive integer Sets the number of seconds the menu remains visible before selecting the default option. The default value is usually 5 in many distributions.

The other piece of the puzzle is GRUB_TIMEOUT_STYLE. With menu, the menu is displayed and the time counts down on the screen; with hidden, time runs hidden. If you want to always see the menu, set menu. If you prefer to hide it but give a window to press a key, you can play with hidden and a time greater than zero, although the most direct way to debug is to use menu and positive time.

Also remember that some remnants of old configurations with GRUB_HIDDEN_TIMEOUT may interfere. Comment them with # It is a safe practice to prevent them from being triggered if your distribution still reads them somehow. In general, modern setup focuses on / Etc / default / grub and in regenerating with update-grub.

Display the on-demand menu during boot

Even with the hidden menu, many boards and firmwares allow force its appearance with a key. In traditional BIOS systems, hold down the key Shift right after the BIOS screen; on UEFI computers, it usually works I. This trick is very useful when you don't want to permanently change the settings but need to occasionally access advanced options.

If it doesn't work the first time, try restarting and pressing the key a little earlier. the exact moment in which it should be maintained can vary from one team to another. Have it clearly configured GRUB_TIMEOUT_STYLE=menu It's still the cleanest solution, but this shortcut can get you out of a tight spot. Don't rule it out if you urgently need to enter an older kernel or recovery mode.

Reference and additional documentation

To go deeper into the configuration, the available variables and their syntax, you can consult the GRUB Texinfo manual in the section (grub) Top > Configuration > Simple configuration. It is the official source and will help you understand why certain combinations work the way they do, as well as cover less common options that we don't usually touch on a daily basis.

And remember: if after editing /etc/default/grub the changes are not reflected, please reconfirm that you have executed sudo update-grub no errors and restarted. If the problem persists, check video parameters, custom entries, and the presence of files indicating whether you are using GRUB2 or Legacy in /boot/grub. A methodical verification usually solves 99% of cases.

You already know how to force menu visibility, adjust the wait time to your liking, and what to do when nothing seems to work. From setting GRUB_TIMEOUT_STYLE and special values From using Grub Customizer to fine-tuning video parameters, you have a full range of solutions at your fingertips to get the GRUB menu back to normal whenever you want.