d-i partman-auto/disk string /dev/sda
d-i partman-auto/method string regular
d-i partman-lvm/device_remove_lvm boolean true
d-i partman-md/device_remove_md boolean true
d-i partman-lvm/confirm boolean true
d-i partman-auto/expert_recipe string sdc :: \
                500 10000 1000000 ext4 \
                $primary{ } \
                $bootable{ } \
                method{ format } \
                format{ } \
                use_filesystem{ } \
                filesystem{ ext4 } \
                mountpoint{ / } \
        . \
        64 512 2048 linux-swap \
                $primary{ } \
                method{ swap } \
                format{ } \
        .
d-i partman-auto/choose_recipe select sdc
d-i partman/default_filesystem string ext4
d-i partman/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