How can I display the grub during boot?

So, I had a dual boot and just nuked the windows partitions, and then got rid of the boot files for windows and updated the grub, and now my PC boots directly into ubuntu. However, I'd like to still have the grub option so I can switch between kernels, and I want to make it permanent.

I've read about the matter and what I found was advice to comment the following line out of the grub file:

GRUB_HIDDEN_TIMEOUT=0

However, there is no such line in the file, which sole content is:

# 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_STYLE=hidden
GRUB_TIMEOUT=10
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
GRUB_CMDLINE_LINUX=""
# Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...)
#GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef"
# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL=console
# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command `vbeinfo'
#GRUB_GFXMODE=640x480
# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux
#GRUB_DISABLE_LINUX_UUID=true
# Uncomment to disable generation of recovery mode menu entries
#GRUB_DISABLE_RECOVERY="true"
# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE="480 440 1"

What does this mean? Should I instead comment out the GRUB_TIMEOUT_STYLE=hidden line, or what?

1 Answer

Edit the file /etc/default/grub, and find this line:

 GRUB_TIMEOUT_STYLE=hidden

Change that line to:

GRUB_TIMEOUT_STYLE=menu

and most importantly, after making that change, save the file and run:

 sudo update-grub

sometimes if grub is not installed properly you may need

if boot is legacy

sudo grub-install /dev/sdx

or

sudo grub-install --force /dev/sdx

sdx being the boot drive sda,sdb or sdc If boot is EFI you need to specify where your EFI System partition is mounted:

 sudo grub-install --efi-directory=<address of efi-directory (eg. /mnt/efi)>