Bon, puisque tu veux voir un multi-boot, voici le mien ( Windows 10 + Fedora 27 + Centos 7 ) :
[fifi@localhost ~]$ su -
Mot de passe :
[root@localhost ~]# cat /boot/grub2/grub.cfg
#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by grub2-mkconfig using templates
# from /etc/grub.d and settings from /etc/default/grub
#
### BEGIN /etc/grub.d/00_header ###
set pager=1
if [ -f ${config_directory}/grubenv ]; then
load_env -f ${config_directory}/grubenv
elif [ -s $prefix/grubenv ]; then
load_env
fi
if [ "${next_entry}" ] ; then
set default="${next_entry}"
set next_entry=
save_env next_entry
set boot_once=true
else
set default="${saved_entry}"
fi
if [ x"${feature_menuentry_id}" = xy ]; then
menuentry_id_option="--id"
else
menuentry_id_option=""
fi
export menuentry_id_option
if [ "${prev_saved_entry}" ]; then
set saved_entry="${prev_saved_entry}"
save_env saved_entry
set prev_saved_entry=
save_env prev_saved_entry
set boot_once=true
fi
function savedefault {
if [ -z "${boot_once}" ]; then
saved_entry="${chosen}"
save_env saved_entry
fi
}
function load_video {
if [ x$feature_all_video_module = xy ]; then
insmod all_video
else
insmod efi_gop
insmod efi_uga
insmod ieee1275_fb
insmod vbe
insmod vga
insmod video_bochs
insmod video_cirrus
fi
}
if [ x$feature_default_font_path = xy ] ; then
font=unicode
else
insmod part_msdos
insmod ext2
set root='hd0,msdos3'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos3 --hint-efi=hd0,msdos3 --hint-baremetal=ahci0,msdos3 d325e864-f689-42ce-be5e-6e3fbf0952b6
else
search --no-floppy --fs-uuid --set=root d325e864-f689-42ce-be5e-6e3fbf0952b6
fi
font="/usr/share/grub/unicode.pf2"
fi
if loadfont $font ; then
set gfxmode=1280x1024x32
load_video
insmod gfxterm
set locale_dir=$prefix/locale
set lang=fr_BE
insmod gettext
fi
terminal_output gfxterm
insmod part_msdos
insmod ext2
set root='hd0,msdos3'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos3 --hint-efi=hd0,msdos3 --hint-baremetal=ahci0,msdos3 d325e864-f689-42ce-be5e-6e3fbf0952b6
else
search --no-floppy --fs-uuid --set=root d325e864-f689-42ce-be5e-6e3fbf0952b6
fi
insmod gfxmenu
loadfont ($root)/boot/grub2/themes/system/DejaVuSans-10.pf2
loadfont ($root)/boot/grub2/themes/system/DejaVuSans-12.pf2
loadfont ($root)/boot/grub2/themes/system/DejaVuSans-Bold-14.pf2
loadfont ($root)/boot/grub2/themes/system/DejaVuSans-Bold-16.pf2
loadfont ($root)/boot/grub2/fonts/unicode.pf2
insmod png
set theme=($root)/boot/grub2/themes/system/theme.txt
export theme
if [ x$feature_timeout_style = xy ] ; then
set timeout_style=menu
set timeout=5
# Fallback normal timeout code in case the timeout_style feature is
# unavailable.
else
set timeout=5
fi
### END /etc/grub.d/00_header ###
### BEGIN /etc/grub.d/01_users ###
if [ -f ${prefix}/user.cfg ]; then
source ${prefix}/user.cfg
if [ -n "${GRUB2_PASSWORD}" ]; then
set superusers="root"
export superusers
password_pbkdf2 root ${GRUB2_PASSWORD}
fi
fi
### END /etc/grub.d/01_users ###
### BEGIN /etc/grub.d/10_linux ###
menuentry 'Fedora (4.14.14-300.fc27.x86_64) 27 (Twenty Seven)' --class fedora --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-4.14.7-300.fc27.x86_64-advanced-d325e864-f689-42ce-be5e-6e3fbf0952b6' {
load_video
set gfxpayload=keep
insmod gzio
insmod part_msdos
insmod ext2
set root='hd0,msdos3'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos3 --hint-efi=hd0,msdos3 --hint-baremetal=ahci0,msdos3 d325e864-f689-42ce-be5e-6e3fbf0952b6
else
search --no-floppy --fs-uuid --set=root d325e864-f689-42ce-be5e-6e3fbf0952b6
fi
linux16 /boot/vmlinuz-4.14.14-300.fc27.x86_64 root=UUID=d325e864-f689-42ce-be5e-6e3fbf0952b6 ro rhgb quiet LANG=fr_BE.UTF-8
initrd16 /boot/initramfs-4.14.14-300.fc27.x86_64.img
}
menuentry 'Fedora (4.14.13-300.fc27.x86_64) 27 (Twenty Seven)' --class fedora --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-4.14.7-300.fc27.x86_64-advanced-d325e864-f689-42ce-be5e-6e3fbf0952b6' {
load_video
set gfxpayload=keep
insmod gzio
insmod part_msdos
insmod ext2
set root='hd0,msdos3'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos3 --hint-efi=hd0,msdos3 --hint-baremetal=ahci0,msdos3 d325e864-f689-42ce-be5e-6e3fbf0952b6
else
search --no-floppy --fs-uuid --set=root d325e864-f689-42ce-be5e-6e3fbf0952b6
fi
linux16 /boot/vmlinuz-4.14.13-300.fc27.x86_64 root=UUID=d325e864-f689-42ce-be5e-6e3fbf0952b6 ro rhgb quiet LANG=fr_BE.UTF-8
initrd16 /boot/initramfs-4.14.13-300.fc27.x86_64.img
}
menuentry 'Fedora (4.14.11-300.fc27.x86_64) 27 (Twenty Seven)' --class fedora --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-4.14.7-300.fc27.x86_64-advanced-d325e864-f689-42ce-be5e-6e3fbf0952b6' {
load_video
set gfxpayload=keep
insmod gzio
insmod part_msdos
insmod ext2
set root='hd0,msdos3'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos3 --hint-efi=hd0,msdos3 --hint-baremetal=ahci0,msdos3 d325e864-f689-42ce-be5e-6e3fbf0952b6
else
search --no-floppy --fs-uuid --set=root d325e864-f689-42ce-be5e-6e3fbf0952b6
fi
linux16 /boot/vmlinuz-4.14.11-300.fc27.x86_64 root=UUID=d325e864-f689-42ce-be5e-6e3fbf0952b6 ro rhgb quiet LANG=fr_BE.UTF-8
initrd16 /boot/initramfs-4.14.11-300.fc27.x86_64.img
}
menuentry 'Fedora (0-rescue-a2d62158c5194b7b8f8bab3ee69bb2ae) 27 (Twenty Seven)' --class fedora --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-0-rescue-a2d62158c5194b7b8f8bab3ee69bb2ae-advanced-d325e864-f689-42ce-be5e-6e3fbf0952b6' {
load_video
insmod gzio
insmod part_msdos
insmod ext2
set root='hd0,msdos3'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos3 --hint-efi=hd0,msdos3 --hint-baremetal=ahci0,msdos3 d325e864-f689-42ce-be5e-6e3fbf0952b6
else
search --no-floppy --fs-uuid --set=root d325e864-f689-42ce-be5e-6e3fbf0952b6
fi
linux16 /boot/vmlinuz-0-rescue-a2d62158c5194b7b8f8bab3ee69bb2ae root=UUID=d325e864-f689-42ce-be5e-6e3fbf0952b6 ro rhgb quiet
initrd16 /boot/initramfs-0-rescue-a2d62158c5194b7b8f8bab3ee69bb2ae.img
}
if [ "x$default" = 'Fedora (4.14.7-300.fc27.x86_64) 27 (Twenty Seven)' ]; then default='Advanced options for Fedora>Fedora (4.14.7-300.fc27.x86_64) 27 (Twenty Seven)'; fi;
### END /etc/grub.d/10_linux ###
### BEGIN /etc/grub.d/20_linux_xen ###
### END /etc/grub.d/20_linux_xen ###
### BEGIN /etc/grub.d/20_ppc_terminfo ###
### END /etc/grub.d/20_ppc_terminfo ###
### BEGIN /etc/grub.d/30_os-prober ###
menuentry 'Windows 10 (sur /dev/sda1)' --class windows --class os $menuentry_id_option 'osprober-chain-F6FAA8CBFAA88987' {
insmod part_msdos
insmod ntfs
set root='hd0,msdos1'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1 F6FAA8CBFAA88987
else
search --no-floppy --fs-uuid --set=root F6FAA8CBFAA88987
fi
parttool ${root} hidden-
drivemap -s (hd0) ${root}
chainloader +1
}
menuentry 'CentOS Linux 7 (Core) (sur /dev/sdb9)' --class centos --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-simple-383c0e26-b0bc-416d-ab8f-b046edb669c5' {
insmod part_msdos
insmod ext2
set root='hd0,msdos9'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd1,msdos9 --hint-efi=hd1,msdos9 --hint-baremetal=ahci1,msdos9 --hint='hd0,msdos9' 383c0e26-b0bc-416d-ab8f-b046edb669c5
else
search --no-floppy --fs-uuid --set=root 383c0e26-b0bc-416d-ab8f-b046edb669c5
fi
linux16 /boot/vmlinuz-3.10.0-693.11.1.el7.x86_64 root=UUID=383c0e26-b0bc-416d-ab8f-b046edb669c5 ro vconsole.font=latarcyrheb-sun16 vconsole.keymap=be-latin1 crashkernel=auto rhgb quiet LANG=fr_BE.UTF-8
initrd16 /boot/initramfs-3.10.0-693.11.1.el7.x86_64.img
}
submenu 'Options avancées pour CentOS Linux 7 (Core) (sur /dev/sdb9)' $menuentry_id_option 'osprober-gnulinux-advanced-383c0e26-b0bc-416d-ab8f-b046edb669c5' {
menuentry 'CentOS Linux (3.10.0-693.11.1.el7.x86_64) 7 (Core) (sur /dev/sdb9)' --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-/boot/vmlinuz-3.10.0-693.11.1.el7.x86_64--383c0e26-b0bc-416d-ab8f-b046edb669c5' {
insmod part_msdos
insmod ext2
set root='hd0,msdos9'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd1,msdos9 --hint-efi=hd1,msdos9 --hint-baremetal=ahci1,msdos9 --hint='hd0,msdos9' 383c0e26-b0bc-416d-ab8f-b046edb669c5
else
search --no-floppy --fs-uuid --set=root 383c0e26-b0bc-416d-ab8f-b046edb669c5
fi
linux16 /boot/vmlinuz-3.10.0-693.11.1.el7.x86_64 root=UUID=383c0e26-b0bc-416d-ab8f-b046edb669c5 ro vconsole.font=latarcyrheb-sun16 vconsole.keymap=be-latin1 crashkernel=auto rhgb quiet LANG=fr_BE.UTF-8
initrd16 /boot/initramfs-3.10.0-693.11.1.el7.x86_64.img
}
menuentry 'CentOS Linux (3.10.0-514.16.1.el7.x86_64) 7 (Core) (sur /dev/sdb9)' --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-/boot/vmlinuz-3.10.0-514.16.1.el7.x86_64--383c0e26-b0bc-416d-ab8f-b046edb669c5' {
insmod part_msdos
insmod ext2
set root='hd0,msdos9'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd1,msdos9 --hint-efi=hd1,msdos9 --hint-baremetal=ahci1,msdos9 --hint='hd0,msdos9' 383c0e26-b0bc-416d-ab8f-b046edb669c5
else
search --no-floppy --fs-uuid --set=root 383c0e26-b0bc-416d-ab8f-b046edb669c5
fi
linux16 /boot/vmlinuz-3.10.0-514.16.1.el7.x86_64 root=UUID=383c0e26-b0bc-416d-ab8f-b046edb669c5 ro vconsole.font=latarcyrheb-sun16 vconsole.keymap=be-latin1 crashkernel=auto rhgb quiet LANG=fr_BE.UTF-8
initrd16 /boot/initramfs-3.10.0-514.16.1.el7.x86_64.img
}
menuentry 'CentOS Linux (3.10.0-514.2.2.el7.x86_64) 7 (Core) (sur /dev/sdb9)' --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-/boot/vmlinuz-3.10.0-514.2.2.el7.x86_64--383c0e26-b0bc-416d-ab8f-b046edb669c5' {
insmod part_msdos
insmod ext2
set root='hd0,msdos9'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd1,msdos9 --hint-efi=hd1,msdos9 --hint-baremetal=ahci1,msdos9 --hint='hd0,msdos9' 383c0e26-b0bc-416d-ab8f-b046edb669c5
else
search --no-floppy --fs-uuid --set=root 383c0e26-b0bc-416d-ab8f-b046edb669c5
fi
linux16 /boot/vmlinuz-3.10.0-514.2.2.el7.x86_64 root=UUID=383c0e26-b0bc-416d-ab8f-b046edb669c5 ro vconsole.font=latarcyrheb-sun16 vconsole.keymap=be-latin1 crashkernel=auto rhgb quiet LANG=fr_BE.UTF-8
initrd16 /boot/initramfs-3.10.0-514.2.2.el7.x86_64.img
}
menuentry 'CentOS Linux (3.10.0-327.36.3.el7.x86_64) 7 (Core) (sur /dev/sdb9)' --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-/boot/vmlinuz-3.10.0-327.36.3.el7.x86_64--383c0e26-b0bc-416d-ab8f-b046edb669c5' {
insmod part_msdos
insmod ext2
set root='hd0,msdos9'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd1,msdos9 --hint-efi=hd1,msdos9 --hint-baremetal=ahci1,msdos9 --hint='hd0,msdos9' 383c0e26-b0bc-416d-ab8f-b046edb669c5
else
search --no-floppy --fs-uuid --set=root 383c0e26-b0bc-416d-ab8f-b046edb669c5
fi
linux16 /boot/vmlinuz-3.10.0-327.36.3.el7.x86_64 root=UUID=383c0e26-b0bc-416d-ab8f-b046edb669c5 ro vconsole.font=latarcyrheb-sun16 vconsole.keymap=be-latin1 crashkernel=auto rhgb quiet LANG=fr_BE.UTF-8
initrd16 /boot/initramfs-3.10.0-327.36.3.el7.x86_64.img
}
menuentry 'CentOS Linux (3.10.0-327.28.3.el7.x86_64) 7 (Core) (sur /dev/sdb9)' --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-/boot/vmlinuz-3.10.0-327.28.3.el7.x86_64--383c0e26-b0bc-416d-ab8f-b046edb669c5' {
insmod part_msdos
insmod ext2
set root='hd0,msdos9'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd1,msdos9 --hint-efi=hd1,msdos9 --hint-baremetal=ahci1,msdos9 --hint='hd0,msdos9' 383c0e26-b0bc-416d-ab8f-b046edb669c5
else
search --no-floppy --fs-uuid --set=root 383c0e26-b0bc-416d-ab8f-b046edb669c5
fi
linux16 /boot/vmlinuz-3.10.0-327.28.3.el7.x86_64 root=UUID=383c0e26-b0bc-416d-ab8f-b046edb669c5 ro vconsole.font=latarcyrheb-sun16 vconsole.keymap=be-latin1 crashkernel=auto rhgb quiet LANG=fr_BE.UTF-8
initrd16 /boot/initramfs-3.10.0-327.28.3.el7.x86_64.img
}
menuentry 'CentOS Linux, with Linux 0-rescue-24c3b56165344df28f31b56669e4536f (sur /dev/sdb9)' --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-/boot/vmlinuz-0-rescue-24c3b56165344df28f31b56669e4536f--383c0e26-b0bc-416d-ab8f-b046edb669c5' {
insmod part_msdos
insmod ext2
set root='hd0,msdos9'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd1,msdos9 --hint-efi=hd1,msdos9 --hint-baremetal=ahci1,msdos9 --hint='hd0,msdos9' 383c0e26-b0bc-416d-ab8f-b046edb669c5
else
search --no-floppy --fs-uuid --set=root 383c0e26-b0bc-416d-ab8f-b046edb669c5
fi
linux16 /boot/vmlinuz-0-rescue-24c3b56165344df28f31b56669e4536f root=UUID=383c0e26-b0bc-416d-ab8f-b046edb669c5 ro vconsole.font=latarcyrheb-sun16 vconsole.keymap=be-latin1 crashkernel=auto rhgb quiet
initrd16 /boot/initramfs-0-rescue-24c3b56165344df28f31b56669e4536f.img
}
}
### END /etc/grub.d/30_os-prober ###
### BEGIN /etc/grub.d/40_custom ###
# 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 'SystemRescueCD 5.1.2' {
set iso="/iso/systemrescuecd-x86-5.1.2.iso"
loopback loop (hd0,msdos3)/iso/systemrescuecd-x86-5.1.2.iso
linux (loop)/isolinux/rescue64 setkmap=be irqpoll isoloop=/iso/systemrescuecd-x86-5.1.2.iso
initrd (loop)/isolinux/initram.igz
}
### END /etc/grub.d/40_custom ###
### BEGIN /etc/grub.d/41_custom ###
if [ -f ${config_directory}/custom.cfg ]; then
source ${config_directory}/custom.cfg
elif [ -z "${config_directory}" -a -f $prefix/custom.cfg ]; then
source $prefix/custom.cfg;
fi
### END /etc/grub.d/41_custom ###
[root@localhost ~]#
Ou, si tu préfères des captures d'écran :

Une capture de gparted de mon ssd ( Centos est sur mon hdd ) :

Pas encore convaincu que c'est possible ?
Si c'est sur ton sda8 que tu veux installer Fedora, sans séparer la /home de la /, tu choisis Partitionnement personnalisé, tu sélectionnes le sda8, tu le formates en Ext4 ( tu n'auras donc pas de lvm ) et tu auras toute l'installation de Fedora sur cette partititon ( /boot, /, /home ...etc )
Si tu veux Fedora seule sur ton disque ( comme tu sembles le demander dans #1) : tu supprimes, avec Gparted toutes tes partitions et lors de l'installation avec Anaconda, partitionnement personnalisé et puis tu crées la ou les partitions que tu veux ( /boot, /, /home, swap ...) ou tu le fais avant avec gparted ( perso, c'est ce que j'ai fait )
https://doc.fedora-fr.org/wiki/Guide_d%27installation_de_Fedora_en_images#Partitionnement