Reduction of Linux boot time - Adjust GRUB TIMEOUT

In many Linux distributions, the Grand Unified Bootloader (GRUB) waits five seconds before using the default boot entry to continue booting. This article shows how to reduce the boot time by adapting the GRUB_TIMEOUT setting by five seconds.

GRUB configuration file /etc/default/grub

The five-second wait time is set in the file /etc/default/grub (GRUB_TIMEOUT=5):

# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
#   info -f grub -n 'Simple configuration'

GRUB_DEFAULT=0
GRUB_TIMEOUT=5
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet"
GRUB_CMDLINE_LINUX=""

Reduction of boot time: GRUB_TIMEOUT=0

To reduce time for the startup, timeout must be changed on 1 to 2 seconds (for example with sudo vi /etc/default/grub):

GRUB_TIMEOUT=0

Execute the update-grub command with root rights: sudo update-grub

The new timeout value will be active the next time the system is started.

Author: Werner Fischer Werner Fischer, working in the Knowledge Transfer team at Thomas-Krenn, completed his studies of Computer and Media Security at FH Hagenberg in Austria. He is a regular speaker at many conferences like LinuxTag, OSMC, OSDC, LinuxCon, and author for various IT magazines. In his spare time he enjoys playing the piano and training for a good result at the annual Linz marathon relay.

Translator: Alina Ranzinger Alina has been working at Thomas-Krenn.AG since 2024. After her training as multilingual business assistant, she got her job as assistant of the Product Management and is responsible for the translation of texts and for the organisation of the department.