Erreur

Debian No EFI partition was found

Exemple de conf OK en mode UEFI (testé avec Debian 10)

### Contents of the preconfiguration file
d-i debian-installer/language string en
d-i debian-installer/country string FR
d-i debian-installer/locale string en_US.UTF-8
d-i localechooser/supported-locales multiselect en_US.UTF-8, fr_FR.UTF-8

### Keyboard
d-i keyboard-configuration/xkb-keymap select fr
d-i keyboard-configuration/xkb-keymap select fr(latin9)
d-i console-keymaps-at/keymap select fr

# keymap is an alias for keyboard-configuration/xkb-keymap
#d-i keymap select fr(latin9)

### Network configuration
d-i netcfg/choose_interface select auto
d-i netcfg/get_hostname string debianxx
d-i netcfg/get_domain string localdomain
d-i netcfg/wireless_wep string
d-i debian-installer/add-kernel-opts string biosdevname=0 net.ifnames=0

### Other
d-i hw-detect/load_firmware boolean false

#### Apt mirror
d-i mirror/country string manual
d-i apt-setup/no_mirror boolean true

### Account setup
d-i passwd/root-login boolean false
d-i passwd/make-user boolean true
#d-i passwd/root-password password toor
#d-i passwd/root-password-again password toor
d-i passwd/user-fullname string Process
d-i passwd/username string jean
d-i passwd/user-password password P@ssw0rd
d-i passwd/user-password-again password P@ssw0rd

### Clock and time zone setup
d-i clock-setup/utc boolean true
d-i time/zone string Europe/Paris
d-i clock-setup/ntp boolean true
d-i clock-setup/ntp-server string 192.168.20.34, 192.168.21.34

#### Partitioning
d-i partman-efi/non_efi_system boolean true                    
d-i partman-auto/method string lvm
d-i partman-lvm/confirm boolean true
d-i partman-lvm/confirm_nooverwrite boolean true
d-i partman-auto-lvm/new_vg_name string vgos
d-i partman-auto/disk string /dev/sda
d-i partman-auto/expert_recipe string                         \
      boot-root ::                                            \
              513 1024 1024 ext4                              \
                      $primary{ }                             \
                      $bootable{ }                            \
                      method{ format } format{ }              \
                      use_filesystem{ } filesystem{ ext4 }    \
                      mountpoint{ /boot }                     \
                      options/noatime{ noatime }              \
              .                                               \
              512 512 512 vfat                                \
                      $primary{ }                             \
                      method{ efi } format{ }                 \
                      mountpoint{ /boot/efi }                 \
                      options/noatime{ noatime }              \
              .                                               \
              2048 6144 6144 ext4                             \
                      $lvmok{ }                               \
                      method{ format } format{ }              \
                      use_filesystem{ } filesystem{ ext4 }    \
                      mountpoint{ / }                         \
                      options/noatime{ noatime }              \
                      lv_name{ root }                         \
              .                                               \
              2048 4096 4096 ext4                             \
                      $lvmok{ }                               \
                      method{ format } format{ }              \
                      use_filesystem{ } filesystem{ ext4 }    \
                      mountpoint{ /var }                      \
                      options/noatime{ noatime }              \
                      lv_name{ var }                          \
              .                                               \
              1024 1024 1024 ext4                             \
                      $lvmok{ }                               \
                      method{ format } format{ }              \
                      use_filesystem{ } filesystem{ ext4 }    \
                      mountpoint{ /opt }                      \
                      options/noatime{ noatime }              \
                      lv_name{ opt }                          \
              .                                               \
              1024 1024 2048 ext4                             \
                      $lvmok{ }                               \
                      method{ format } format{ }              \
                      use_filesystem{ } filesystem{ ext4 }    \
                      mountpoint{ /var/log }                  \
                      options/noatime{ noatime }              \
                      lv_name{ log }                          \
              .                                               \
              2048 2048 2048 ext4                             \
                      $lvmok{ }                               \
                      method{ format } format{ }              \
                      use_filesystem{ } filesystem{ ext4 }    \
                      mountpoint{ /home }                     \
                      options/noatime{ noatime }              \
                      lv_name{ home }                         \
              .                                               \
              1024 1024 1024 linux-swap                       \
                      $lvmok{ }                               \
                      method{ swap } format{ }                \
                      lv_name{ swap }                         \
              .                                               \
              1024 -1 -1 ext4                                 \
                      $lvmok{ }                               \
                      method{ format } format{ }              \
                      use_filesystem{ } filesystem{ ext4 }    \
                      mountpoint{ /tmp/willbeautoremoved }    \
                      lv_name{ willbeautoremoved }            \
              .                                               \


d-i partman-partitioning/confirm_write_new_label boolean true
d-i partman/choose_partition select finish
d-i partman/confirm boolean true
d-i partman/confirm_nooverwrite boolean true
d-i partman-md/confirm boolean true
d-i partman/mount_style select uuid

### Base system installation
d-i base-installer/install-recommends boolean false

### Apt setup
apt-cdrom-setup apt-setup/cdrom/set-first boolean false
apt-cdrom-setup apt-setup/cdrom/set-next  boolean false
d-i apt-setup/contrib boolean false
d-i apt-setup/use_mirror boolean false
d-i apt-setup/services-select multiselect

### Package selection
tasksel tasksel/first multiselect standard
d-i pkgsel/upgrade select safe-upgrade
popularity-contest popularity-contest/participate boolean false
d-i pkgsel/include string openssh-server # kbd console-data

### Grub
d-i grub-installer/only_debian boolean true
d-i grub-installer/with_other_os boolean false
#d-i grub-installer/bootdev  string /dev/sda
# To install to the first device (assuming it is not a USB stick):
d-i grub-installer/bootdev string default

# Finish install
d-i finish-install/reboot_in_progress note
d-i cdrom-detect/eject boolean true

# Postinstall
d-i preseed/late_command string \
    in-target mkdir /root/.ssh ; \
    in-target mkdir /root/preseed ; \
    cp /cdrom/preseed/authorized_keys /target/root/.ssh/ ; \
    in-target chown -R root:root /root/ ; \
    in-target chmod -R go-rwx /root/.ssh/authorized_keys ; \
    in-target apt-get clean ; \
    cp /cdrom/preseed/* /target/root/preseed ; \
    in-target chmod +x /root/preseed/firstboot.sh ; \
    cp /cdrom/preseed/rc.local /target/etc/rc.local ; \
    echo "/var/tmp /tmp    none bind 0 0" >> /target/etc/fstab ; \
    in-target chmod +x /etc/rc.local ;