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|
#!/bin/sh
#
# $FreeBSD$
#
# Packages to install into the image we're creating. This is a deliberately
# minimalist set, providing only the packages necessary to bootstrap further
# package installation as specified via EC2 user-data.
export VM_EXTRA_PACKAGES="ec2-scripts firstboot-freebsd-update firstboot-pkgs isc-dhcp44-client ebsnvme-id"
# Include the amazon-ssm-agent package in amd64 images, since some users want
# to be able to use it on systems which are not connected to the Internet.
# (It is not enabled by default, however.) This package does not exist for
# aarch64, so we have to be selective about when we install it.
if [ "${TARGET_ARCH}" = "amd64" ]; then
export VM_EXTRA_PACKAGES="${VM_EXTRA_PACKAGES} amazon-ssm-agent"
fi
# Set to a list of third-party software to enable in rc.conf(5).
export VM_RC_LIST="ec2_configinit ec2_fetchkey ec2_loghostkey firstboot_freebsd_update firstboot_pkgs ntpd dev_aws_disk"
# Build with a 4.9 GB UFS partition; the growfs rc.d script will expand
# the partition to fill the root disk after the EC2 instance is launched.
# Note that if this is set to <N>G, we will end up with an <N+1> GB disk
# image since VMSIZE is the size of the UFS partition, not the disk which
# it resides within.
export VMSIZE=5000m
# No swap space; the ec2_ephemeralswap rc.d script will allocate swap
# space on EC2 ephemeral disks. (If they exist -- the T2 low-cost instances
# and the C4 compute-optimized instances don't have ephemeral disks. But
# it would be silly to bloat the image and increase costs for every instance
# just for those two families, especially since instances ranging in size
# from 1 GB of RAM to 60 GB of RAM would need different sizes of swap space
# anyway.)
export NOSWAP=YES
vm_extra_pre_umount() {
# The firstboot_pkgs rc.d script will download the repository
# catalogue and install or update pkg when the instance first
# launches, so these files would just be replaced anyway; removing
# them from the image allows it to boot faster.
mount -t devfs devfs ${DESTDIR}/dev
chroot ${DESTDIR} ${EMULATOR} env ASSUME_ALWAYS_YES=yes \
/usr/sbin/pkg delete -f -y pkg
umount ${DESTDIR}/dev
rm ${DESTDIR}/var/db/pkg/repo-*.sqlite
# The size of the EC2 root disk can be configured at instance launch
# time; expand our filesystem to fill the disk.
echo 'growfs_enable="YES"' >> ${DESTDIR}/etc/rc.conf
# EC2 instances use DHCP to get their network configuration. IPv6
# requires accept_rtadv.
echo 'ifconfig_DEFAULT="SYNCDHCP accept_rtadv"' >> ${DESTDIR}/etc/rc.conf
# Unless the system has been configured via EC2 user-data, the user
# will need to SSH in to do anything.
echo 'sshd_enable="YES"' >> ${DESTDIR}/etc/rc.conf
# The AWS CLI tools are generally useful, and small enough that they
# will download quickly; but users will often override this setting
# via EC2 user-data.
echo 'firstboot_pkgs_list="awscli"' >> ${DESTDIR}/etc/rc.conf
# Enable IPv6 on all interfaces, and spawn DHCPv6 via rtsold
echo 'ipv6_activate_all_interfaces="YES"' >> ${DESTDIR}/etc/rc.conf
echo 'rtsold_enable="YES"' >> ${DESTDIR}/etc/rc.conf
echo 'rtsold_flags="-M /usr/local/libexec/rtsold-M -a"' >> ${DESTDIR}/etc/rc.conf
# Provide a script which rtsold can use to launch DHCPv6
mkdir -p ${DESTDIR}/usr/local/libexec
cat > ${DESTDIR}/usr/local/libexec/rtsold-M <<'EOF'
#!/bin/sh
/usr/local/sbin/dhclient -6 -nw -N -cf /dev/null $1
EOF
chmod 755 ${DESTDIR}/usr/local/libexec/rtsold-M
# The EC2 console is output-only, so while printing a backtrace can
# be useful, there's no point dropping into a debugger or waiting
# for a keypress.
echo 'debug.trace_on_panic=1' >> ${DESTDIR}/boot/loader.conf
echo 'debug.debugger_on_panic=0' >> ${DESTDIR}/boot/loader.conf
echo 'kern.panic_reboot_wait_time=0' >> ${DESTDIR}/boot/loader.conf
# The console is not interactive, so we might as well boot quickly.
echo 'autoboot_delay="-1"' >> ${DESTDIR}/boot/loader.conf
echo 'beastie_disable="YES"' >> ${DESTDIR}/boot/loader.conf
# The emulated keyboard attached to EC2 instances is inaccessible to
# users, and there is no mouse attached at all; disable to keyboard
# and the keyboard controller (to which the mouse would attach, if
# one existed) in order to save time in device probing.
echo 'hint.atkbd.0.disabled=1' >> ${DESTDIR}/boot/loader.conf
echo 'hint.atkbdc.0.disabled=1' >> ${DESTDIR}/boot/loader.conf
# EC2 has two consoles: An emulated serial port ("system log"),
# which has been present since 2006; and a VGA console ("instance
# screenshot") which was introduced in 2016.
echo 'boot_multicons="YES"' >> ${DESTDIR}/boot/loader.conf
# Some older EC2 hardware used a version of Xen with a bug in its
# emulated serial port. It is not clear if EC2 still has any such
# nodes, but apply the workaround just in case.
echo 'hw.broken_txfifo="1"' >> ${DESTDIR}/boot/loader.conf
# Load the kernel module for the Amazon "Elastic Network Adapter"
echo 'if_ena_load="YES"' >> ${DESTDIR}/boot/loader.conf
# Use the "nda" driver for accessing NVMe disks rather than the
# historical "nvd" driver.
echo 'hw.nvme.use_nvd="0"' >> ${DESTDIR}/boot/loader.conf
# Disable ChallengeResponseAuthentication according to EC2
# requirements.
sed -i '' -e \
's/^#ChallengeResponseAuthentication yes/ChallengeResponseAuthentication no/' \
${DESTDIR}/etc/ssh/sshd_config
# Use FreeBSD Update and Portsnap mirrors hosted in AWS
sed -i '' -e 's/update.FreeBSD.org/aws.update.FreeBSD.org/' \
${DESTDIR}/etc/freebsd-update.conf
sed -i '' -e 's/portsnap.FreeBSD.org/aws.portsnap.FreeBSD.org/' \
${DESTDIR}/etc/portsnap.conf
# Use the NTP service provided by Amazon
sed -i '' -e 's/^pool/#pool/' \
-e '1,/^#server/s/^#server.*/server 169.254.169.123 iburst/' \
${DESTDIR}/etc/ntp.conf
# Provide a map for accessing Elastic File System mounts
cat > ${DESTDIR}/etc/autofs/special_efs <<'EOF'
#!/bin/sh
if [ $# -eq 0 ]; then
# No way to know which EFS filesystems exist and are
# accessible to this EC2 instance.
exit 0
fi
# Provide instructions on how to mount the requested filesystem.
FS=$1
REGION=`fetch -qo- http://169.254.169.254/latest/meta-data/placement/availability-zone | sed -e 's/[a-z]$//'`
echo "-nfsv4,minorversion=1,oneopenown ${FS}.efs.${REGION}.amazonaws.com:/"
EOF
chmod 755 ${DESTDIR}/etc/autofs/special_efs
# The first time the AMI boots, the installed "first boot" scripts
# should be allowed to run:
# * ec2_configinit (download and process EC2 user-data)
# * ec2_fetchkey (arrange for SSH using the EC2-provided public key)
# * growfs (expand the filesystem to fill the provided disk)
# * firstboot_freebsd_update (install critical updates)
# * firstboot_pkgs (install packages)
touch ${DESTDIR}/firstboot
if ! [ -z "${QEMUSTATIC}" ]; then
rm -f ${DESTDIR}/${EMULATOR}
fi
rm -f ${DESTDIR}/etc/resolv.conf
return 0
}
|
