@Bougron, voici un exemple d'installation de xenial minimal dans un sous-volume btrfs sous Archlinux.
arch-chroot est spécifique à Archlinux, c'est juste un script qui monte rbind les répertoires systèmes de /mnt avant d'appliquer la commande chroot.
Tu noteras le dialogue d'installation de Grub demandant la confirmation de sa non installation en programme de démarrage.
[frankenstein@FRANKENSTEIN ~]$ pkexec btrfs subvolume list /
ID 257 gen 109417 top level 5 path @
ID 258 gen 109417 top level 5 path @home
ID 259 gen 106792 top level 5 path @data
ID 591 gen 106766 top level 257 path var/lib/machines
ID 662 gen 106790 top level 5 path @-backup
ID 663 gen 106791 top level 5 path @home-backup
ID 664 gen 106792 top level 5 path @data-backup
[frankenstein@FRANKENSTEIN ~]$ pkexec mount -t btrfs /dev/sda3 /mnt
[frankenstein@FRANKENSTEIN ~]$ pkexec btrfs subvolume create /mnt/@xenial
Create subvolume '/mnt/@xenial'
[frankenstein@FRANKENSTEIN ~]$ pkexec btrfs subvolume list /
ID 257 gen 109420 top level 5 path @
ID 258 gen 109419 top level 5 path @home
ID 259 gen 106792 top level 5 path @data
ID 591 gen 106766 top level 257 path var/lib/machines
ID 662 gen 106790 top level 5 path @-backup
ID 663 gen 106791 top level 5 path @home-backup
ID 664 gen 106792 top level 5 path @data-backup
ID 665 gen 109420 top level 5 path @xenial
[frankenstein@FRANKENSTEIN ~]$ pkexec umount /mnt
[frankenstein@FRANKENSTEIN ~]$ pkexec mount -t btrfs -o subvol=@xenial /dev/sda3 /mnt
[frankenstein@FRANKENSTEIN ~]$ pkexec debootstrap xenial /mnt http://archive.ubuntu.com/ubuntu/
W: Cannot check Release signature; keyring file not available /usr/share/keyrings/ubuntu-archive-keyring.gpg
I: Retrieving Release
I: Retrieving Packages
I: Validating Packages
I: Resolving dependencies of required packages...
I: Resolving dependencies of base packages...
I: Checking component main on http://archive.ubuntu.com/ubuntu...
I: Retrieving adduser 3.113+nmu3ubuntu4
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I: Configuring dh-python...
I: Configuring libc-bin...
I: Configuring systemd...
I: Configuring initramfs-tools...
I: Configuring ureadahead...
I: Configuring resolvconf...
I: Base system installed successfully.
[frankenstein@FRANKENSTEIN ~]$ pkexec arch-chroot /mnt
# echo $PATH
/usr/sbin:/usr/bin:/sbin:/bin:/root/bin
# passwd
Enter new UNIX password:
Retype new UNIX password:
passwd: password updated successfully
# apt-get update
Get:1 http://archive.ubuntu.com/ubuntu xenial InRelease [247 kB]
Get:2 http://archive.ubuntu.com/ubuntu xenial/main Translation-en [568 kB]
Fetched 814 kB in 1s (614 kB/s)
Reading package lists... Done
# apt-get install linux-generic
Reading package lists... Done
Building dependency tree... Done
The following additional packages will be installed:
crda dbus gettext-base grub-common grub-gfxpayload-lists grub-pc grub-pc-bin grub2-common iw libasprintf0v5 libcap-ng0 libdbus-1-3 libdbus-glib-1-2 libfreetype6 libfuse2
libglib2.0-0 libglib2.0-data libicu55 libnl-3-200 libnl-genl-3-200 libxml2 linux-firmware linux-headers-4.4.0-21 linux-headers-4.4.0-21-generic linux-headers-generic
linux-image-4.4.0-21-generic linux-image-extra-4.4.0-21-generic linux-image-generic os-prober sgml-base shared-mime-info thermald wireless-regdb xdg-user-dirs xml-core
Suggested packages:
dbus-user-session | dbus-x11 multiboot-doc grub-emu xorriso desktop-base fuse fdutils linux-doc-4.4.0 | linux-source-4.4.0 linux-tools sgml-base-doc debhelper
The following NEW packages will be installed:
crda dbus gettext-base grub-common grub-gfxpayload-lists grub-pc grub-pc-bin grub2-common iw libasprintf0v5 libcap-ng0 libdbus-1-3 libdbus-glib-1-2 libfreetype6 libfuse2
libglib2.0-0 libglib2.0-data libicu55 libnl-3-200 libnl-genl-3-200 libxml2 linux-firmware linux-generic linux-headers-4.4.0-21 linux-headers-4.4.0-21-generic
linux-headers-generic linux-image-4.4.0-21-generic linux-image-extra-4.4.0-21-generic linux-image-generic os-prober sgml-base shared-mime-info thermald wireless-regdb
xdg-user-dirs xml-core
0 upgraded, 36 newly installed, 0 to remove and 0 not upgraded.
Need to get 115 MB of archives.
After this operation, 481 MB of additional disk space will be used.
Do you want to continue? [Y/n] Y
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Package configuration
┌──────────────────────────────────────────────────────────────────────────┤ Configuring grub-pc ├──────────────────────────────────────────────────────────────────────────┐
│ The grub-pc package is being upgraded. This menu allows you to select which devices you'd like grub-install to be automatically run for, if any. │
│ │
│ Running grub-install automatically is recommended in most situations, to prevent the installed GRUB core image from getting out of sync with GRUB modules or grub.cfg. │
│ │
│ If you're unsure which drive is designated as boot drive by your BIOS, it is often a good idea to install GRUB to all of them. │
│ │
│ Note: it is possible to install GRUB to partition boot records as well, and some appropriate partitions are offered here. However, this forces GRUB to use the blocklist │
│ mechanism, which makes it less reliable, and therefore is not recommended. │
│ │
│ GRUB install devices: │
│ │
│ [ ] /dev/sda (500107 MB; ???) │
│ [ ] - /dev/sda3 (487707 MB; /) │
│ [ ] /dev/sdb (1000202 MB; ???) │
│ │
│ │
│ <Ok> │
│ │
└───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
Package configuration
┌──────────────────────────────────────────────────────────────────────────┤ Configuring grub-pc ├──────────────────────────────────────────────────────────────────────────┐
│ │
│ You chose not to install GRUB to any devices. If you continue, the boot loader may not be properly configured, and when this computer next starts up it will use │
│ whatever was previously in the boot sector. If there is an earlier version of GRUB 2 in the boot sector, it may be unable to load modules or handle the current │
│ configuration file. │
│ │
│ If you are already using a different boot loader and want to carry on doing so, or if this is a special environment where you do not need a boot loader, then you should │
│ continue anyway. Otherwise, you should install GRUB somewhere. │
│ │
│ Continue without installing GRUB? │
│ │
│ <Yes> <No> │
│ │
└───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
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Creating config file /etc/default/grub with new version
/usr/bin/locale: Cannot set LC_CTYPE to default locale: No such file or directory
/usr/bin/locale: Cannot set LC_MESSAGES to default locale: No such file or directory
/usr/bin/locale: Cannot set LC_ALL to default locale: No such file or directory
Setting up grub-gfxpayload-lists (0.7) ...
Processing triggers for libc-bin (2.23-0ubuntu3) ...
Processing triggers for ureadahead (0.100.0-19) ...
Processing triggers for systemd (229-4ubuntu4) ...
Processing triggers for sgml-base (1.26+nmu4ubuntu1) ...
Processing triggers for dbus (1.10.6-1ubuntu3) ...
# ls /
bin boot dev etc home initrd.img lib lib64 media mnt opt proc root run sbin srv sys tmp usr var vmlinuz
# exit
/bin/sh: 7: Cannot set tty process group (No such process)
[frankenstein@FRANKENSTEIN ~]$
Ceci est un exemple avec activation de l'utilisateur root sans création de /etc/fstab qui en réalité est optionnel pour peu que tu n'utilises qu'une seule partition Ubuntu et que tu précises l'option rw au chargement du noyau linux , la partition swap est maintenant montée automatiquement par SystemD.
Penser à configurer le clavier système, ce que je n'ai pas fait.
Tu as maintenant un Ubuntu Minimal fonctionnel, tu n'as plus qu'à le démarrer par le moyen de ton choix.
Tu peux égalemenent continuer en chroot l'installation de ton environnement de bureau préféré.
C'est relativement simple pour un utilisateur comme toi.
