我在使用预安装的 Ubuntu 时遇到问题，它给出错误“没有定义根文件系统”。
有人知道这是为什么吗？
d-i partman-basicfilesystems/choose_label string gpt
d-i partman-basicfilesystems/default_label string gpt
d-i partman-partitioning/choose_label string gpt
d-i partman-partitioning/default_label string gpt
d-i partman/choose_label string gpt
d-i partman/default_label string gpt
partman-partitioning partman-partitioning/choose_label select gpt
d-i partman-auto/disk string /dev/$(lsblk -lbn --output SIZE,NAME | sort -n | tail -n 1 | cut -d" " -f2)"
d-i partman-auto/method string regular
d-i partman-md/device_remove_md boolean true
d-i partman-lvm/device_remove_lvm boolean true
d-i partman-lvm/device_remove_lvm_span boolean true
d-i partman-auto/purge_lvm_from_device boolean true
d-i partman-lvm/confirm boolean true
d-i partman-lvm/confirm_nooverwrite boolean true
d-i partman-auto/expert_recipe string \
boot-root :: \
300 300 300 ext3 \
$primary{ } $bootable{ } \
method{ format } format{ } \
use_filesystem{ } filesystem{ ext4 } \
mountpoint{ /boot } \
. \
80000 80000 80000 ext4 \
method{ format } format{ } \
use_filesystem{ } filesystem{ ext4 } \
mountpoint{ / } \
. \
1000 100000 -1 ext4 \
method{ format } format{ } \
use_filesystem{ } filesystem{ ext4 } \
mountpoint{ /home } \
. \
2000 2000 2000 linux-swap \
method{ swap } format{ } \
. \
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
