Need to do some work in the black & white command line console? You can press Ctrl+Alt+F3 on keyboard to switch from the current session to tty3 text console, and switch back via Ctrl+Alt+F2.

From the startup grub boot-loader menu entry, you may select the Advanced Options > recovery mode > Drop to root shell prompt to get into text mode. However you need to run command mount -o rw,remount / to get file system write permission.

If you want to make Ubuntu automatically boot into the text mode, configure grub settings by doing following steps one by one:

1. Open terminal and run command to backup the configuration file:

sudo cp -n /etc/default/grub /etc/default/grub.backup

2. Edit the configuration file via command:

sudo gedit /etc/default/grub

When the file opens, do:

• disable GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" by adding # at the beginning.
• set GRUB_CMDLINE_LINUX="" to GRUB_CMDLINE_LINUX="text"
• remove # from the line GRUB_TERMINAL="console" to disable graphical terminal.

3. Save the file and apply changes by running command:

sudo update-grub

4. One more command is required as Ubuntu now uses systemd:

sudo systemctl set-default multi-user.target

How to Restore:

To restore changes, simply move back the backup file via command:

sudo mv /etc/default/grub.backup /etc/default/grub

And run sudo update-grub to apply change.

Also change the setting back in systemd via command:

sudo systemctl set-default graphical.target