Change the default start up option and wait option time on Ubuntu 18.04

Abstract

This article aims to record how to change the default start up option and wait option time in Ubuntu 18.04 with grub settings.

Note: Though this is for Ubuntu 18.04, it may still adapt to the similar version like Ubuntu 16.04.

Step 1. Edit grub file

Edit the grub file to config the start up grub settings in the file /etc/default/grub with command:

sudo vim /etc/default/grub

Step 2. Change the default start up option

The option GRUB_DEFAULT defines which option is to start up as default. So change the number to the index of the option want to set as default. For example, if we want to start up the first option as default, we set like this:

GRUB_DEFAULT=0

Step 3. Change the default wait option time

The option GRUB_TIMEOUT defines the time of wait for user choosing option. So change the value to change the waiting time. For example, if we want to change the waiting time to 2 seconds, we set like this:

GRUB_TIMEOUT=2

Step 4. Save and update the configuration

Save and exit the file, and update the grub configuration with command:

sudo update-grub