From c9d4b4a69a7ad4a5f2039c4edcc433e3dafcc2b4 Mon Sep 17 00:00:00 2001
From: Vitaliy Filippov <vitalif@yourcmc.ru>
Date: Tue, 28 Jan 2020 19:41:23 +0300
Subject: [PATCH] Simple script to prepare a diskless PXE/NFS Debian Buster

---
 .gitignore    |   1 +
 debian_nfs.sh | 118 ++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 119 insertions(+)
 create mode 100644 .gitignore
 create mode 100755 debian_nfs.sh

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..05b023b
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+authorized_keys
diff --git a/debian_nfs.sh b/debian_nfs.sh
new file mode 100755
index 0000000..68a6194
--- /dev/null
+++ b/debian_nfs.sh
@@ -0,0 +1,118 @@
+#!/bin/bash
+# Prepare diskless NFS Debian Buster with tmpfs overlay
+# The idea is just to boot a node and expose SSH
+# NFS export is /home/nfsboot
+# TFTP root is /home/tftp
+
+set -e
+
+SERVER=172.31.1.5
+SUBNET=172.31.1.0/24
+
+CFG=`dirname $0`/debian_nfs.conf
+[ -f "$CFG" ] && . $CFG
+
+apt-get -y install pxelinux syslinux-common nfs-kernel-server dnsmasq
+
+echo "/home/nfsboot $SUBNET(ro,no_root_squash)" >> /etc/exports
+
+service nfs-kernel-server restart
+service rpcbind restart
+
+cat >/etc/dnsmasq.conf <<EOF
+port=0
+log-dhcp
+enable-tftp
+tftp-root=/home/tftp
+dhcp-boot=pxelinux.0
+pxe-service=x86PC,"Network Boot",pxelinux
+dhcp-range=${SUBNET%%/*},proxy
+#dhcp-host=70:85:C2:CE:B5:43,net:allow
+#dhcp-ignore=tag:!known
+EOF
+
+service dnsmasq restart
+
+mkdir -p /home/tftp
+cp /usr/lib/PXELINUX/pxelinux.0 /home/tftp
+cp /usr/lib/syslinux/modules/bios/ldlinux.c32 /home/tftp
+mkdir -p /home/nfsboot
+debootstrap buster /home/nfsboot
+
+git clone https://github.com/chesty/overlayroot /home/overlayroot
+mkdir -p /home/nfsboot/etc/initramfs-tools/hooks
+mkdir -p /home/nfsboot/etc/initramfs-tools/scripts/init-bottom
+cp /home/overlayroot/hooks-overlay /home/nfsboot/etc/initramfs-tools/hooks/
+cp /home/overlayroot/init-bottom-overlay /home/nfsboot/etc/initramfs-tools/scripts/init-bottom/
+
+mkdir -p /home/nfsboot/root/.ssh
+cp `dirname $0`/authorized_keys /home/nfsboot/root/.ssh
+
+chroot /home/nfsboot <<EOF
+
+echo net-client > /etc/hostname
+
+ln -s /proc/mounts /etc/mtab
+
+echo 'deb http://http.debian.net/debian buster main contrib non-free' > /etc/apt/sources.list
+echo 'APT::Install-Recommends "false";' > /etc/apt/apt.conf
+echo 'APT::Install-Suggests "false";' >> /etc/apt/apt.conf
+echo en_US.UTF-8 UTF-8 > /etc/locale.gen
+echo ru_RU.UTF-8 UTF-8 >> /etc/locale.gen
+
+apt-get update
+apt-get install -y network-manager mc less git wget ca-certificates zip unzip curl smartmontools hdparm python3 bzip2 xz-utils file debootstrap \
+  openssh-server locales nfs-common linux-image-amd64 firmware-linux firmware-linux-nonfree firmware-amd-graphics firmware-realtek firmware-bnx2 firmware-bnx2x busybox
+
+echo '/dev/nfs / nfs tcp,nolock,ro,soft 0 0' > /etc/fstab
+echo 'tmpfs /tmp tmpfs defaults 0 0' >> /etc/fstab
+rm -rf /var/tmp
+ln -s /tmp /var/tmp
+
+if ! grep -q "^overlay" /etc/initramfs-tools/modules; then
+    echo overlay >> /etc/initramfs-tools/modules
+fi
+
+cat >/etc/initramfs-tools/initramfs.conf <<EE
+MODULES=netboot
+BUSYBOX=auto
+KEYMAP=n
+COMPRESS=gzip
+DEVICE=
+NFSROOT=auto
+BOOT=nfs
+EE
+
+update-initramfs -u -k all
+
+rm -f /etc/ssh/ssh_host*
+
+cat >/etc/rc.local <<EE
+#!/bin/bash
+
+ssh-keygen -A
+systemctl restart ssh
+exit 0
+EE
+chmod 755 /etc/rc.local
+
+EOF
+
+cp /home/nfsboot/boot/vmlinuz-* /home/tftp
+cp /home/nfsboot/boot/initrd.img-* /home/tftp
+cd /home/tftp
+VMLINUZ=`ls -t vmlinuz-*|head -n1`
+INITRD=`ls -t initrd.img-*|head -n1`
+mkdir -p pxelinux.cfg
+cat >pxelinux.cfg/default <<EOF
+# boot diskless debian
+default menu.c32
+prompt 0
+menu title pc-client
+ontimeout debian_buster
+timeout 5
+label debian_buster
+  menu label $VMLINUZ debian buster
+  kernel $VMLINUZ
+  append root=/dev/nfs initrd=$INITRD nfsroot=$SERVER:/home/nfsboot ro nomodeset ipv6.disable=1
+EOF