尝试为Ubuntu 18.04 Desktop amd64创建自动安装，但是RAID-1配置存在问题。
给出的错误消息是：No root file system is defined.
/ var / log / syslog错误消息是：
ubuntu partman: No matching physical volumes found.
ubuntu partman: Reading volume groups from cache
list-devices显示/ dev / sda和/ dev / sdb确实存在并且是正确的驱动器。
Partman Preseed配置：
# Set Raid
d-i partman-auto/disk string /dev/sda /dev/sdb
d-i partman-auto/method string raid
# Clean any previous config
d-i partman-lvm/device_remove_lvm boolean true
d-i partman-auto/purge_lvm_from_device boolean true
d-i partman-md/device_remove_md boolean true
d-i partman-md/confirm_nochanges boolean true
d-i partman-lvm/confirm boolean true
# Set Partition recipes
d-i partman-auto/choose_recipe select boot-root
d-i partman-auto-lvm/new_vg_name string vg01
d-i partman-auto-lvm/guided_size string 100%
# Raid Config
d-i partman-auto-raid/recipe string \
1 2 0 ext3 /boot /dev/sda2#/dev/sdb2 \
. \
1 2 0 lvm - /dev/sda3#/dev/sdb3 \
.
# Partition / LVM config
d-i partman-auto/expert_recipe string \
boot-root :: \
1 1 1 free \
$iflabel{ gpt } \
method{ biosgrub } \
. \
256 10 256 raid \
$lvmignore{ } \
$primary{ } \
method{ raid } \
. \
1000 20 1000000 raid \
$lvmignore{ } \
$primary{ } \
method{ raid } \
. \
150% 30 150% swap \
$defaultignore{ } \
$lvmok{ } \
lv_name{ lv_swap } \
method{ swap } \
format{ } \
. \
20480 40 20480 ext4 \
$defaultignore{ } \
$lvmok{ } \
lv_name{ lv_root } \
method{ format } \
format{ } \
use_filesystem{ } \
filesystem{ ext4 } \
mountpoint{ / } \
. \
1 50 -1 ext4 \
$defaultignore{ } \
$lvmok{ } \
lv_name{ lv_dummy } \
.
# Opts for completing Partition Setup.
d-i mdadm/boot_degraded boolean true
d-i partman-md/confirm boolean true
d-i partman-partitioning/confirm_write_new_label boolean true
d-i partman/choose_partition select Finish partitioning and write changes to disk
d-i partman/confirm boolean true
d-i partman-md/confirm_nooverwrite boolean true
d-i partman/confirm_nooverwrite boolean true
此伙伴配置来自this github repo