Ubuntu 16.04: NFSを使ったシンクライアントのPXE Bootサーバをインストールする

#!/bin/sh

set -e

# Change the following variable to yours.
[ -z "${SERVER_IPADDR}" ] && \
  SERVER_IPADDR=$(hostname -I | awk '{ print $1 }')
[ -z "${DHCP_SERVER_INTERFACESv4}" ] && DHCP_SERVER_INTERFACESv4=ens3
[ -z "${DHCP_SUBNET}" ] && DHCP_SUBNET=192.168.11.0
[ -z "${DHCP_NETMASK}" ] && DHCP_NETMASK=255.255.255.0
[ -z "${DHCP_DOMAIN}" ] && DHCP_DOMAIN=hiroom2.com
[ -z "${DHCP_DNS}" ] && DHCP_DNS="192.168.11.2, 192.168.11.1"
[ -z "${DHCP_ROUTER}" ] && DHCP_ROUTER=192.168.11.1
[ -z "${DHCP_CLIENT_HOSTNAME}" ] && \
  DHCP_CLIENT_HOSTNAME=ubuntu-1604-pxeboot-client
[ -z "${DHCP_CLIENT_IPADDR}" ] && DHCP_CLIENT_IPADDR=192.168.11.254
[ -z "${DHCP_CLIENT_MACADDR}" ] && DHCP_CLIENT_MACADDR=52:54:00:5e:7a:a4

tftpd_hpa_install()
{
  sudo apt install -y tftpd-hpa
  sudo systemctl enable tftpd-hpa
  sudo systemctl restart tftpd-hpa
}

isc_dhcp_server_install()
{
  sudo apt install -y isc-dhcp-server

  sudo sed -e 's/^#DHCPDv4_CONF=/DHCPDv4_CONF=/g' \
       -e 's/^#DHCPDv4_PID=/DHCPDv4_PID=/g' \
       -e "s/INTERFACESv4=\"\"/INTERFACESv4=\"${DHCP_SERVER_INTERFACESv4}\"/g" \
       -i /etc/default/isc-dhcp-server

  cat <<EOF | sudo tee /etc/dhcp/dhcpd.conf
subnet ${DHCP_SUBNET} netmask ${DHCP_NETMASK} {
  option domain-name "${DHCP_DOMAIN}";
  option domain-name-servers ${DHCP_DNS};
  option routers ${DHCP_ROUTER};
  next-server ${SERVER_IPADDR};
  filename "pxelinux.0";
}

host ${DHCP_CLIENT_HOSTNAME} {
  hardware ethernet ${DHCP_CLIENT_MACADDR};
  fixed-address ${DHCP_CLIENT_IPADDR};
}
EOF

  sudo systemctl restart isc-dhcp-server
}

nfs_kernel_server_install()
{
  # Set NFS server.
  sudo apt install -y nfs-kernel-server debootstrap systemd-container
  sudo mkdir /var/lib/nfsroot
  echo "/var/lib/nfsroot *(rw,sync,no_root_squash,no_subtree_check)" | \
    sudo tee /etc/exports
  sudo exportfs -ra

  # Create root filesystem.
  URL=$(grep "^deb .* xenial main" /etc/apt/sources.list | awk '{ print $2 }')
  sudo debootstrap xenial /var/lib/nfsroot "${URL}"

  # Get debconf from server for locale and keyboard.
  sudo apt install -y debconf-utils systemd-container
  sudo debconf-get-selections | grep locale | \
    sudo tee /var/lib/nfsroot/debconf.txt
  sudo debconf-get-selections | grep keyboard-configuration | \
    sudo tee -a /var/lib/nfsroot/debconf.txt
  sudo cp /etc/locale* /var/lib/nfsroot/etc/
  sudo cp /etc/default/locale /var/lib/nfsroot/etc/default/

  # resolv.conf is not updated by systemd-nspawn.
  sudo cp /etc/resolv.conf /var/lib/nfsroot/etc/resolv.conf.server

  sudo systemd-nspawn -D /var/lib/nfsroot sh -c "
set -e

# Use server resolv.conf.
rm -f /etc/resolv.conf
mv /etc/resolv.conf.server /etc/resolv.conf

apt update -y
apt upgrade -y

# Set debconf to client for locale and keyboard.
cat debconf.txt | debconf-set-selections
apt install --reinstall -y locales keyboard-configuration
rm -f debconf.txt

# Install kernel and create initrd.
apt install -y initramfs-tools linux-image-generic
cat <<EOF > /etc/initramfs-tools/initramfs.conf
MODULES=netboot
BUSYBOX=auto
KEYMAP=n
COMPRESS=gzip
DEVICE=
NFSROOT=${SERVER_IPADDR}:/var/lib/nfsroot
BOOT=nfs
EOF
update-initramfs -tu

# Install Unity and OpenSSH server.
apt install -y ubuntu-desktop unity openssh-server

# Set root password and create user.
useradd -m -s /bin/bash ubuntu
yes ubuntu | passwd ubuntu
gpasswd -a ubuntu sudo

# systemd needs /etc/fstab entry too while using nfsroot.
echo '${SERVER_IPADDR}:/var/lib/nfsroot / nfs defaults 0 0' > /etc/fstab

sudo sed -e 's/^dns=dnsmasq/#dns=dnsmasq/g' \
     -i /etc/NetworkManager/NetworkManager.conf

# Generate /etc/resolv.conf with dhclient.
rm -f /etc/resolv.conf
ln -s /run/resolvconf/resolv.conf /etc/resolv.conf
cat <<EOF > /etc/rc.local
#!/bin/sh -e
dhclient
EOF
"
}

pxelinux_install()
{
  cd /var/lib/tftpboot

  sudo apt install -y pxelinux syslinux
  sudo cp -a /usr/lib/syslinux/modules/bios .
  sudo cp /usr/lib/PXELINUX/pxelinux.0 .
  sudo cp /usr/lib/syslinux/modules/bios/ldlinux.c32 .
  sudo cp /var/lib/nfsroot/vmlinuz .
  sudo chmod 744 vmlinuz
  sudo cp /var/lib/nfsroot/initrd.img .
  sudo chmod 744 initrd.img

  sudo mkdir pxelinux.cfg
  cat <<EOF | sudo tee pxelinux.cfg/default
path bios
include menu.cfg
default bios/vesamenu.c32
prompt 0
timeout 10
EOF

  cat <<EOF | sudo tee menu.cfg
menu hshift 13
menu width 49
menu margin 8
menu tabmsg

menu title Thin client boot menu
label ubuntu-1604-thin-client
  menu label ^Ubuntu 16.04 thin client
  kernel vmlinuz
  append vga=788 initrd=initrd.img ip=dhcp nfsroot=${SERVER_IPADDR}:/var/lib/nfsroot rw
menu end
EOF
}

pxeboot_main()
{
  tftpd_hpa_install
  isc_dhcp_server_install
  nfs_kernel_server_install
  pxelinux_install
}

pxeboot_main