Preseed partitioning example

gistfile1.txt

# Keyboard and locale
d-i debian-installer/locale string en_US
d-i console-setup/ask_detect boolean false
d-i keyboard-configuration/layoutcode string us

# Network
d-i netcfg/choose_interface select eth0
d-i hw-detect/load_firmware boolean true

# Mirror
d-i mirror/country string manual
d-i mirror/http/hostname string mirror.anl.gov
d-i mirror/http/directory string /pub/ubuntu
d-i mirror/http/proxy string

# Clock
d-i clock-setup/utc boolean true
d-i time/zone string UTC

# Partitioning
d-i partman-auto/disk string /dev/sda
d-i partman-auto/method string lvm
d-i partman-auto/purge_lvm_from_device boolean true
d-i partman-lvm/confirm 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/expert_recipe string   \
    boot-root ::                        \
        100 5000 -1 ext4                \
            $defaultignore{ }           \
            $primary{ }                 \
            method{ lvm }               \
            device{ /dev/sda }          \
            vg_name{ openstack }        \
        .                               \
        512 1000 1000 ext4              \
            $primary{ }                 \
            $bootable{ }                \
            method{ format }            \
            format{ }                   \
            use_filesystem{ }           \
            filesystem{ ext4 }          \
            mountpoint{ /boot }         \
        .                               \
        128000 50 128000 linux-swap     \
            method{ swap }              \
            format{ }                   \
        .                               \
        20000 60 50000 ext4             \
            $lvmok{ }                   \
            lv_name{ root }             \
            method{ format }            \
            format{ }                   \
            use_filesystem{ }           \
            filesystem{ ext4 }          \
            in_vg{ openstack }          \
            mountpoint{ / }             \
        .               \
        1000000 70 -1 ext4              \
            $lvmok{ }                   \
            lv_name{ var }              \
            method{ format }            \
            format{ }                   \
            use_filesystem{ }           \
            filesystem{ ext4 }          \
            in_vg{ openstack }          \
            mountpoint{ /var }          \
        .

d-i partman-auto/choose_recipe select boot-root
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-auto/init_automatically_partition select biggest_free
d-i partman/confirm_nooverwrite boolean true
d-i partman-lvm/confirm_nooverwrite boolean true
d-i partman-auto-lvm/guided_size string max

# Set to true if you want to encrypt the first user's home directory.
d-i user-setup/encrypt-home boolean false

# Users

# Kernel params

# Late command

# etc etc