image-builder

#!/bin/sh
# set -x # In case you want to see what  actually I am doing
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############################ CHANGE THE FOLLOWING ##############################
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BSD_ARCH="amd64"
BSD_VERSION="13.1"
# Possible distributions
# base-dbg.txz kernel-dbg.txz lib32-dbg.txz lib32.txz ports.txz src.txz tests.txz
DISTRIBUTIONS="base.txz kernel.txz"; export DISTRIBUTIONS
HOSTNAME="FreeBSD"
PASSWORD="FreeBSD"
# These ports are  installed by Vultr. If you want to add more just keep on adding
PKGNG="ca_root_nss libnghttp2 libssh2 python wget"
SIZE_GB=4
SIZE_SWAP=0         # Change size in GB. o to disable
SSH_KEY="<INSERT YOUR SSH KEY>"
TIMEZONE=UTC
################################################################################
########################  DO NOT CHANGE THE FOLLOWING ##########################
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DISTDIR=distdir-${BSD_VERSION}-${BSD_ARCH}
IMAGENAME=FreeBSD-${BSD_VERSION}-RELEASE-${BSD_ARCH}.raw
MD_NUMBER=79
MIRROR="https://download.freebsd.org/"
PASSWORD_HASH=$(echo ${PASSWORD} | openssl passwd -6 -stdin)
ZROOT="zroot"
ZPOOL_DIR="${ZROOT}/"
SYSRC="sysrc -f /mnt/${ZPOOL_DIR}etc/rc.conf"
SYSCTL_CONF="/mnt/${ZPOOL_DIR}etc/sysctl.conf"

##################################################################################
# Create an empty image
truncate -s ${SIZE_GB}G ${IMAGENAME}

# Create metadevice:
mdconfig -f ${IMAGENAME} -u${MD_NUMBER}

# Partition metadevice
gpart create -s gpt md${MD_NUMBER}
gpart add -a 4k -s 512k -t freebsd-boot md${MD_NUMBER}
gpart add -a 4k -t freebsd-zfs -l gpt_root md${MD_NUMBER}
gpart bootcode -b /boot/pmbr -p /boot/gptzfsboot -i 1 md${MD_NUMBER}
zpool create -f -o altroot=/mnt -o cachefile=/var/tmp/zpool.cache zroot /dev/md${MD_NUMBER}p2
# These are for testing
#zpool export zroot
#zpool import -o altroot=/mnt -o cachefile=/var/tmp/zpool.cache zroot
# a big thanks to this: https://calomel.org/zfs_freebsd_root_install.html
zpool set bootfs=zroot zroot
zpool set listsnapshots=on zroot
zpool set autoreplace=on zroot
zfs set checksum=fletcher4 zroot
zfs set compression=lz4 zroot
zfs set atime=off zroot
zfs set copies=3 zroot
if [ $SIZE_SWAP -ne 0 ]; then
zfs create -V ${SIZE_SWAP}G zroot/swap
zfs set org.freebsd:swap=on zroot/swap
fi

# Create distdir
mkdir -p ${DISTDIR}

# Fetch distfiles
env BSDINSTALL_DISTDIR="$(pwd)"/${DISTDIR} BSDINSTALL_DISTSITE=${MIRROR}/releases/${BSD_ARCH}/${BSD_VERSION}-RELEASE bsdinstall distfetch

# Extract distfiles
env BSDINSTALL_CHROOT=/mnt/${ZPOOL_DIR} BSDINSTALL_DISTDIR="$(pwd)"/${DISTDIR} BSDINSTALL_DISTSITE=${MIRROR}/releases/${BSD_ARCH}/${BSD_VERSION}-RELEASE bsdinstall distextract

# Post-installation config by bsdinstall
env BSDINSTALL_CHROOT=/mnt/${ZPOOL_DIR} BSDINSTALL_DISTDIR="$(pwd)"/${DISTDIR} BSDINSTALL_DISTSITE=${MIRROR}/releases/${BSD_ARCH}/${BSD_VERSION}-RELEASE bsdinstall config

# Common Settings
# Set Hostname
${SYSRC} hostname="${HOSTNAME}"

# Interface Settings
# IPv4
${SYSRC} ifconfig_vtnet0="DHCP -tso"

# IPv6
${SYSRC} ifconfig_vtnet0_ipv6="inet6 accept_rtadv -rxcsum -tso"
${SYSRC} ipv6_activate_all_interfaces="YES"
${SYSRC} rtsold_enable="YES"
${SYSRC} rtsold_flags="-aF"
${SYSRC} static_routes="linklocal"

# Set CMOS clock
touch /mnt/${ZPOOL_DIR}etc/wall_cmos_clock

# Set TimeZone
cp /mnt/${ZPOOL_DIR}usr/share/zoneinfo/${TIMEZONE} /mnt/${ZPOOL_DIR}etc/localtime

# Setup SSH
${SYSRC} sshd_enable="YES"
${SYSRC} sshd_flags="-o PermitRootLogin=without-password"
mkdir -p /mnt/${ZPOOL_DIR}/root/.ssh
echo "${SSH_KEY}" > /mnt/${ZPOOL_DIR}/root/.ssh/authorized_keys

# Set root password
echo "${PASSWORD_HASH}" | chroot /mnt/${ZPOOL_DIR} pw usermod root -H 0

# Set some common values for vultr
${SYSRC} ntpd_enable="YES"
${SYSRC} devmatch_blacklist="virtio_random.ko"
${SYSRC} sendmail_enable="NONE"
${SYSRC} syslogd_flags="-ss"

{
  echo "kern.ipc.maxsockbuf=67108864"
  echo "net.inet.tcp.sendbuf_max=67108864"
  echo "net.inet.tcp.recvbuf_max=67108864"
  echo "net.inet.tcp.sendbuf_auto=1"
  echo "net.inet.tcp.recvbuf_auto=1"
  echo "net.inet.tcp.sendbuf_inc=16384"
  echo "#net.inet.tcp.recvbuf_inc=524288"
  echo "#net.inet.tcp.cc.algorithm=htcp"
} >> ${SYSCTL_CONF}

# Create resolve.conf for pkg installation
echo 'nameserver 9.9.9.9' >> /mnt/${ZPOOL_DIR}/etc/resolv.conf

# pkg bootstrap
if [ -z "${PKGNG}" ]; then
chroot /mnt/${ZPOOL_DIR} pkg bootstrap -y
else
pkg -c /mnt/${ZPOOL_DIR} install -y ${PKGNG}
fi
# Delete resolve.conf after pkg installation
rm /mnt/${ZPOOL_DIR}/etc/resolv.conf

# Setup zfs booting
${SYSRC} zfs_enable="YES"
cp /var/tmp/zpool.cache /mnt/${ZPOOL_DIR}/boot/zfs/zpool.cache
cd /mnt/${ZPOOL_DIR} || exit ; ln -s usr/home home
{
  echo 'vfs.root.mountfrom="zfs:zroot"'
  echo 'kern.geom.label.disk_ident.enable="0"'
  echo 'kern.geom.label.gpt.enable="1"'
  echo 'kern.geom.label.gptid.enable="0"'
  echo 'cryptodev_load="YES"'
  echo 'zfs_load="YES"'
} > /mnt/${ZPOOL_DIR}/boot/loader.conf
rm -f /mnt/${ZPOOL_DIR}/etc/fstab
touch /mnt/${ZPOOL_DIR}/etc/fstab

# Unmount the zfs filesystem before packaging
# To reimport I'd zpool import -o altroot=/mnt [the numeric id] or zroot
sleep 30 # Give it some time replenish it's sync
zpool export -f zroot

# Delete the metadevice
mdconfig -d -u${MD_NUMBER}

echo "Enjoy the image $IMAGENAME"

# vim: ft=sh: