GRUB Menu Not Showing After Fresh Ubuntu Install: Troubleshooting Steps

If you recently installed a fresh Ubuntu system and find that the GRUB menu is not showing up, there are several reasons for this issue, and corresponding solutions to help resolve it. This guide will walk you through some common causes and provide detailed steps to address each one.

Booting Directly into Ubuntu

One of the primary reasons the GRUB menu may not appear is if you booted directly into Ubuntu. When you have only one operating system installed on your system, the GRUB menu might not show up because the system boots directly into the installed OS without displaying the menu. To address this, you can either:

Restart your system and press a key during bootup to manually access the GRUB menu. Add a second operating system or virtual machine for a boot manager.

Fast Boot Configuration

In some systems, the GRUB menu might be hidden due to fast boot settings. This setting is often enabled in BIOS/UEFI to improve system startup speed but can prevent the GRUB menu from appearing. To disable this and show the GRUB menu, follow these steps:

Open a terminal by pressing Ctrl Alt T. Edit the GRUB configuration file:

Run the command:

sudo nano /etc/default/grub

Look for the line:

GRUB_TIMEOUT0

Change it to a higher value, such as 5 seconds:

GRUB_TIMEOUT5

Ensure the line GRUB_HIDDEN_TIMEOUT0 is either commented out or set to false:

#GRUB_HIDDEN_TIMEOUTfalse

Save and exit the editor.

Update the GRUB configuration with:

Run the command:

sudo update-grub

UEFI vs. Legacy Mode

An important factor in GRUB not appearing is the boot mode your system is using. If your system uses UEFI, ensure that the boot order in your BIOS/UEFI settings is set to boot from the UEFI version of GRUB. If you installed Ubuntu in UEFI mode but your system is trying to boot in Legacy BIOS mode, GRUB might be bypassed. Adjust your BIOS/UEFI settings accordingly.

Reinstalling GRUB

If the GRUB bootloader is installed incorrectly, you may need to reinstall it using a live USB session. Here's how to do it:

Boot from the live USB. Open a terminal and mount your Ubuntu partition:

Run the command:

sudo mount /dev/sdXn /mnt

Replace sdXn with your actual partition (e.g., sda1). Reinstall GRUB:

Run the command:

sudo grub-install --boot-directory/mnt/boot /dev/sdX

Replace sdX with your drive identifier (e.g., sda). Update GRUB:

Run the command:

sudo update-grub

Graphics Issues

GRUB may not display properly due to graphics driver issues. You can try booting into different video modes by pressing Shift or Esc during startup to access the GRUB menu. This may help resolve issues related to graphics.

If you've tried all these solutions and the GRUB menu still doesn't appear, please provide more details about your installation setup so I can help further troubleshoot the issue.