How to have a custom Grub2 menu that is maintenance free

[Cavsfan]

Right now, I just have a wallpaper added, custom font colors, a default boot menuentry and a longer timeout.
With the way they have added the submenu, after the default menuentry, containing the extra boot entries for a system, that default remains pretty consistent.

[Cavsfan]

Woo Hoo! I am beginning to see how EFI systems can be customized. I just booted into Arch Linux from a custom entry.

Let's see how these other systems work and I'll have more to say.

[Cavsfan]

OK, I successfully booted into Arch Linux, Arch Linux's Fallback kernel, Windows 10, openSUSE Tumbleweed and Bionic Beaver 18.04.1 LTS and all went well.
This is from within Arch Linux though but, the differences should not be much. Just perhaps different on some Linux distributions.
Arch Linux uses the UUID of the EFI system partition as well as the UUID of the Arch partition, for reasons unbeknownst to me.

Here is the custom file I used. I will explain what I did before it's added to the Wiki as I need input from you all to make sure it works first.
Of course I cheat and change that +3 to a +4 so that we can at least see what is between the quotes when doing an update-grub, that and the picture should be the only things you see (a tip Drs305 taught me).

#!/bin/sh
echo 1>&2 "Adding Arch Linux, Windows 10, openSUSE Tumbleweed and Xubuntu Bionic Beaver 18.04 LTS"
exec tail -n +4 $0
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
menuentry 'Arch Linux' --class arch --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-bbca28b2-503e-4dc8-9850-c54bd0492da8' {
    load_video
    set gfxpayload=keep
    insmod gzio
    insmod part_gpt
    insmod fat
    set root='hd2,gpt1'
    search --no-floppy --fs-uuid --set=root 688D-126B
    linux    /vmlinuz-linux root=UUID=bbca28b2-503e-4dc8-9850-c54bd0492da8 rw  quiet
    initrd    /intel-ucode.img /initramfs-linux.img
}
menuentry 'Arch Linux (fallback kernel)' --class arch --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-linux-fallback-bbca28b2-503e-4dc8-9850-c54bd0492da8' {
    load_video
    set gfxpayload=keep
    insmod gzio
    insmod part_gpt
    insmod fat
    set root='hd2,gpt1'
    search --no-floppy --fs-uuid --set=root 688D-126B
    linux    /vmlinuz-linux root=UUID=bbca28b2-503e-4dc8-9850-c54bd0492da8 rw  quiet
    initrd    /initramfs-linux-fallback.img
}
menuentry 'Windows 10' --class windows --class os $menuentry_id_option 'osprober-efi-688D-126B' {
    insmod part_gpt
    insmod fat
    set root='hd2,gpt1'
    search --no-floppy --fs-uuid --set=root 688D-126B
    chainloader /EFI/Microsoft/Boot/bootmgfw.efi
}
menuentry 'openSUSE Tumbleweed' --class opensuse --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-simple-274e3321-d7af-4544-9afa-b1b3c118c325' {
    insmod part_gpt
    insmod ext2
    set root='hd2,gpt7'
    search --no-floppy --fs-uuid --set=root 274e3321-d7af-4544-9afa-b1b3c118c325
    linux /boot/vmlinuz root=/dev/sdc7 splash=silent resume=/dev/disk/by-uuid/be437b2b-9c95-4590-8d32-4da8e6c90318 quiet
    initrd /boot/initrd
}
menuentry 'Ubuntu 18.04.1 LTS' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-simple-899f7460-1d2a-43ab-b98e-5e33953cb0c4' {
    insmod part_gpt
    insmod ext2
    set root='hd2,gpt8'
    search --no-floppy --fs-uuid --set=root 899f7460-1d2a-43ab-b98e-5e33953cb0c4
    linux /vmlinuz root=UUID=899f7460-1d2a-43ab-b98e-5e33953cb0c4 ro quiet splash $vt_handoff
    initrd /initrd.img
}

This is my system:

[cavsfan@ArchLinux ~]$ sudo blkid |grep sdc
[sudo] password for cavsfan: 
/dev/sdc1: UUID="688D-126B" TYPE="vfat" PARTLABEL="EFI system partition" PARTUUID="3c1b6d6f-8a24-43da-b595-8c304ceee48d"
/dev/sdc3: UUID="C4968A52968A44C0" TYPE="ntfs" PARTLABEL="Windows_10" PARTUUID="345c85f4-bce7-4bc7-bbe0-db03eb319cad"
/dev/sdc4: UUID="701AE4631AE427B4" TYPE="ntfs" PARTUUID="1e337754-b45d-45a5-a971-b8cdcae8a002"
/dev/sdc5: UUID="be437b2b-9c95-4590-8d32-4da8e6c90318" TYPE="swap" PARTLABEL="Basic data partition" PARTUUID="3a259867-656d-41ed-9931-cf15a3bd0148"
/dev/sdc6: LABEL="ArchLinux" UUID="bbca28b2-503e-4dc8-9850-c54bd0492da8" TYPE="ext4" PARTLABEL="Arch_Linux" PARTUUID="5312b771-0835-4957-80a6-9a8a7107f24a"
/dev/sdc7: LABEL="opensuse" UUID="274e3321-d7af-4544-9afa-b1b3c118c325" TYPE="ext4" PARTUUID="25d7851a-f45f-4d60-955a-4a31706f8452"
/dev/sdc8: LABEL="Bionic" UUID="899f7460-1d2a-43ab-b98e-5e33953cb0c4" TYPE="ext4" PARTLABEL="Bionic_Beaver" PARTUUID="c4e0fdc9-7eac-4661-a7c6-c5a00c9a46fc"
/dev/sdc10: LABEL="Media" UUID="840ac879-510a-4b8d-be01-9d3a5f37dbb2" TYPE="ext4" PARTLABEL="Media" PARTUUID="61e2e7f9-1a98-44f7-881e-ae85fceaf994"
/dev/sdc2: PARTLABEL="Microsoft reserved partition" PARTUUID="49992d5b-79cd-4934-a12f-11782bb345bd"

So, this should boot an Ubuntu system, just the partitions and UUID needs changed to match your system.

#!/bin/sh
echo 1>&2 "Adding Xubuntu Bionic Beaver 18.04.1 LTS"
exec tail -n +4 $0
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
menuentry 'Ubuntu 18.04.1 LTS' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-simple-899f7460-1d2a-43ab-b98e-5e33953cb0c4' {
    insmod part_gpt
    insmod ext2
    set root='hd2,gpt8'
    search --no-floppy --fs-uuid --set=root 899f7460-1d2a-43ab-b98e-5e33953cb0c4
    linux /vmlinuz root=UUID=899f7460-1d2a-43ab-b98e-5e33953cb0c4 ro quiet splash $vt_handoff
    initrd /initrd.img
}

Right now I see no way to boot Ubuntu to a backup kernel because there is only a /vmlinuz file and no /vmlinuz.old file. Which may be because I haven't had enough kernels get installed yet.

So, this is a tad more complicated than the Legacy/MBR partitioned systems were but, at least you do not have to go to the OS where your grub is installed and update the grub there when a kernel is added to a different system.
Because the default grub has the /vmlinuz and /initrd tied to a kernel number.

A lot if not all of each entry can be copied from the existing /boot/grub/grub.cfg file and then modified, which makes it MUCH easier.

[Cavsfan]

First picture of a customized EFI Grub menu. I just took a picture of the menu, which is sort of small but, could not make out the highlighted color of red taking the whole screen.



All of them work so I made /etc/grub.d/10_linux and /etc/grub.d/30_os-prober unexecutable.

[oldfred]

I use a configfile to boot the grub of my other Ubuntu installs.
And I now like labels over UUID, but you have to manage labels. When I re-install cosmic and reformat partition, it needs label updated.
You can then have two entries, one to directly boot kernel, and one to configfile to that installs grub with all its entries. I only have used configile to other grub so far.

menuentry "Cosmic 18.10 on sdb12" {
    configfile (hd2,gpt12)/boot/grub/grub.cfg
}

menuentry "Cosmic 18.10 on sdb12 test" {
    search --set=root --label cosmic_b --hint hd2,gpt12
    configfile /boot/grub/grub.cfg
}

menuentry 'Live ISOs on SSD' {
search --set=root --label iso_ssd --hint hd1,gpt5
configfile /livecdimage.cfg
} 

menuentry 'Live ISOs on HDD (boot on SSD)' {
configfile (hd1,6)/livecdimage.cfg
}

[Cavsfan]

I use a configfile to boot the grub of my other Ubuntu installs.
And I now like labels over UUID, but you have to manage labels. When I re-install cosmic and reformat partition, it needs label updated.
You can then have two entries, one to directly boot kernel, and one to configfile to that installs grub with all its entries. I only have used configile to other grub so far.

menuentry "Cosmic 18.10 on sdb12" {
    configfile (hd2,gpt12)/boot/grub/grub.cfg
}

menuentry "Cosmic 18.10 on sdb12 test" {
    search --set=root --label cosmic_b --hint hd2,gpt12
    configfile /boot/grub/grub.cfg
}

menuentry 'Live ISOs on SSD' {
search --set=root --label iso_ssd --hint hd1,gpt5
configfile /livecdimage.cfg
} 

menuentry 'Live ISOs on HDD (boot on SSD)' {
configfile (hd1,6)/livecdimage.cfg
}

+1
I never would have guessed you could do that with a config file!

[Cavsfan]

OK, for EFI, I copied the exact code from above into Xubuntu 18.04 and successfully booted into each operating system so I know that it works on Ubuntu.

Guess I'll add it to the Wiki when I can.

Basically everything is the same in /etc/default/grub you just change 2 entries. Also the same in /etc/grub.d/05_debian_theme, the 3 menu colors go after line 122.

It's just the menu entries in /etc/grub.d/06_custom that have drastically changed.

One cannot no longer prevent grub from moving from one system to another if grub is updated and installed on that other system.

It's also best to back up the EFI grub immediately after installing a Ubuntu system if you plan on installing another one.

I have Arch Linux, Windows 10, openSUSE Tumbleweed and Xubuntu 18.04 LTS installed currently and this is what I mean:

cavsfan@cavsfan-Bionic-Beaver:~$ sudo su
[sudo] password for cavsfan:
root@cavsfan-Bionic-Beaver:/home/cavsfan# cd /boot/efi/EFI
root@cavsfan-Bionic-Beaver:/boot/efi/EFI# ls
Arch_grub  bionic  Boot  Microsoft  opensuse  ubuntu

The blue is just meant to denote folders. I copied ubuntu to bionic to back it up.

The grub install command has also changed drastically for EFI as you may as well already know.

sudo grub-install --target=x86_64-efi --efi-directory=/boot/efi/EFI/ubuntu --bootloader-id=ubuntu  --recheck

I am not sure if every system is the same, you just have to look for this root owned/read only ubuntu folder to re-install grub back on Ubuntu.

[Cavsfan]

Since no feedback, I guess I am not going to add EFI booting to the Wiki at this time. Everything you need though is in post #534.

It contains the contents of /etc/grub.d/06_custom for booting to Ubuntu, Arch Linux, openSUSE and Windows 10.

It has worked for me very, very well for quite a while now.

[Cavsfan]

Well, after some time and thought, I think I'll add the menuentries for an UEFI (Unified Extensible Firmware Interface) system (SSD) to the Wiki.

I've learned there are several ways that one could customize the UEFI grub but, the only sure fire way I have been able to do it is with UUIDs.

Everything else is the same: the fonts, background picture. Just the menuentries and the way you install grub is different.
Just like the Legacy/MBR partitioned custom grub, this does not ever require any changes except for the same reasons the Non-UEFI systems would.

I've learned how to customize UEFI grub for Ubuntu, Arch Linux, Fedora and openSUSE. I will only include Ubuntu and Windows 10 in the Wiki though.
If anyone would be interested in any of the others, just ask and I will happily provide that too.

I do not know how long it will take me but, it will be done.

[Cavsfan]

Ok, I figured out what was necessary and what was superfluous in the previous posts I have made about a custom UEFI grub.

I updated the Wiki, only the menuentries and way to install grub has changed on Ubuntu. I have been installing and experiencing many different Linux systems.

I would customize each one and there are various differences from system to system.

I currently have Arch Linux, Fedora 29, openSUSE Tumbleweed, MX Linux 18.1 Continuum, Xubuntu 18.04 LTS and Windows 10.

If anyone is interested in more information about anything whatsoever, post it here.

For example here is how easy one boot entry is for Xubuntu Bionic Beaver 18.04 LTS linking UUIDs:

/dev/sdc4: UUID="bbc771f8-ba61-4e50-aeca-d2754b112aee" TYPE="swap" PARTLABEL="swap" PARTUUID="dc354366-1300-48d4-8a60-133aa2e2ca57"
/dev/sdc9: LABEL="Bionic" UUID="833501fb-4f83-4d51-9903-685d56cb6891" TYPE="ext4" PARTLABEL="Bionic" PARTUUID="4f579967-b025-47dc-b080-64a0865d7165"

menuentry '18.04 LTS (Bionic Beaver) LTS' {
    search --no-floppy --fs-uuid --set=root 833501fb-4f83-4d51-9903-685d56cb6891
    linux /vmlinuz root=UUID=833501fb-4f83-4d51-9903-685d56cb6891 ro quiet resume=/dev/disk/by-uuid/bbc771f8-ba61-4e50-aeca-d2754b112aee splash
    initrd /initrd.img
}

Also, let me know if I have made any mistakes.