1#!/bin/sh 2# 3# 4 5# Packages to install into the image we're creating. This is a deliberately 6# minimalist set, providing only the packages necessary to bootstrap further 7# package installation as specified via EC2 user-data. 8export VM_EXTRA_PACKAGES="${VM_EXTRA_PACKAGES} ec2-scripts \ 9 firstboot-freebsd-update firstboot-pkgs isc-dhcp44-client \ 10 ebsnvme-id" 11 12# Include the amazon-ssm-agent package in amd64 images, since some users want 13# to be able to use it on systems which are not connected to the Internet. 14# (It is not enabled by default, however.) This package does not exist for 15# aarch64, so we have to be selective about when we install it. 16if [ "${TARGET_ARCH}" = "amd64" ]; then 17 export VM_EXTRA_PACKAGES="${VM_EXTRA_PACKAGES} amazon-ssm-agent" 18fi 19 20# Set to a list of third-party software to enable in rc.conf(5). 21export VM_RC_LIST="ec2_configinit ec2_fetchkey ec2_loghostkey firstboot_freebsd_update firstboot_pkgs ntpd dev_aws_disk ec2_ephemeral_swap" 22 23# Build with a 4.9 GB partition; the growfs rc.d script will expand 24# the partition to fill the root disk after the EC2 instance is launched. 25# Note that if this is set to <N>G, we will end up with an <N+1> GB disk 26# image since VMSIZE is the size of the filesystem partition, not the disk 27# which it resides within. 28export VMSIZE=5000m 29 30# No swap space; the ec2_ephemeralswap rc.d script will allocate swap 31# space on EC2 ephemeral disks. (If they exist -- the T2 low-cost instances 32# and the C4 compute-optimized instances don't have ephemeral disks. But 33# it would be silly to bloat the image and increase costs for every instance 34# just for those two families, especially since instances ranging in size 35# from 1 GB of RAM to 60 GB of RAM would need different sizes of swap space 36# anyway.) 37export NOSWAP=YES 38 39vm_extra_pre_umount() { 40 # The firstboot_pkgs rc.d script will download the repository 41 # catalogue and install or update pkg when the instance first 42 # launches, so these files would just be replaced anyway; removing 43 # them from the image allows it to boot faster. 44 mount -t devfs devfs ${DESTDIR}/dev 45 chroot ${DESTDIR} ${EMULATOR} env ASSUME_ALWAYS_YES=yes \ 46 /usr/sbin/pkg delete -f -y pkg 47 umount ${DESTDIR}/dev 48 rm ${DESTDIR}/var/db/pkg/repo-*.sqlite 49 50 # The size of the EC2 root disk can be configured at instance launch 51 # time; expand our filesystem to fill the disk. 52 echo 'growfs_enable="YES"' >> ${DESTDIR}/etc/rc.conf 53 54 # EC2 instances use DHCP to get their network configuration. IPv6 55 # requires accept_rtadv. 56 echo 'ifconfig_DEFAULT="SYNCDHCP accept_rtadv"' >> ${DESTDIR}/etc/rc.conf 57 58 # Unless the system has been configured via EC2 user-data, the user 59 # will need to SSH in to do anything. 60 echo 'sshd_enable="YES"' >> ${DESTDIR}/etc/rc.conf 61 62 # The AWS CLI tools are generally useful, and small enough that they 63 # will download quickly; but users will often override this setting 64 # via EC2 user-data. 65 echo 'firstboot_pkgs_list="devel/py-awscli"' >> ${DESTDIR}/etc/rc.conf 66 67 # Enable IPv6 on all interfaces, and spawn DHCPv6 via rtsold 68 echo 'ipv6_activate_all_interfaces="YES"' >> ${DESTDIR}/etc/rc.conf 69 echo 'rtsold_enable="YES"' >> ${DESTDIR}/etc/rc.conf 70 echo 'rtsold_flags="-M /usr/local/libexec/rtsold-M -a"' >> ${DESTDIR}/etc/rc.conf 71 72 # Turn off IPv6 Duplicate Address Detection; the EC2 networking 73 # configuration makes it unnecessary. 74 echo 'net.inet6.ip6.dad_count=0' >> ${DESTDIR}/etc/sysctl.conf 75 76 # Provide a script which rtsold can use to launch DHCPv6 77 mkdir -p ${DESTDIR}/usr/local/libexec 78 cat > ${DESTDIR}/usr/local/libexec/rtsold-M <<'EOF' 79#!/bin/sh 80 81/usr/local/sbin/dhclient -6 -nw -N -cf /dev/null $1 82EOF 83 chmod 755 ${DESTDIR}/usr/local/libexec/rtsold-M 84 85 # The EC2 console is output-only, so while printing a backtrace can 86 # be useful, there's no point dropping into a debugger or waiting 87 # for a keypress. 88 echo 'debug.trace_on_panic=1' >> ${DESTDIR}/boot/loader.conf 89 echo 'debug.debugger_on_panic=0' >> ${DESTDIR}/boot/loader.conf 90 echo 'kern.panic_reboot_wait_time=0' >> ${DESTDIR}/boot/loader.conf 91 92 # The console is not interactive, so we might as well boot quickly. 93 echo 'autoboot_delay="-1"' >> ${DESTDIR}/boot/loader.conf 94 echo 'beastie_disable="YES"' >> ${DESTDIR}/boot/loader.conf 95 96 # Tell gptboot not to wait 3 seconds for a keypress which won't 97 # arrive either. 98 printf -- "-n\n" > ${DESTDIR}/boot.config 99 100 # The emulated keyboard attached to EC2 instances is inaccessible to 101 # users, and there is no mouse attached at all; disable to keyboard 102 # and the keyboard controller (to which the mouse would attach, if 103 # one existed) in order to save time in device probing. 104 echo 'hint.atkbd.0.disabled=1' >> ${DESTDIR}/boot/loader.conf 105 echo 'hint.atkbdc.0.disabled=1' >> ${DESTDIR}/boot/loader.conf 106 107 # EC2 has two consoles: An emulated serial port ("system log"), 108 # which has been present since 2006; and a VGA console ("instance 109 # screenshot") which was introduced in 2016. 110 echo 'boot_multicons="YES"' >> ${DESTDIR}/boot/loader.conf 111 112 # Some older EC2 hardware used a version of Xen with a bug in its 113 # emulated serial port. It is not clear if EC2 still has any such 114 # nodes, but apply the workaround just in case. 115 echo 'hw.broken_txfifo="1"' >> ${DESTDIR}/boot/loader.conf 116 117 # Load the kernel module for the Amazon "Elastic Network Adapter" 118 echo 'if_ena_load="YES"' >> ${DESTDIR}/boot/loader.conf 119 120 # Use the "nda" driver for accessing NVMe disks rather than the 121 # historical "nvd" driver. 122 echo 'hw.nvme.use_nvd="0"' >> ${DESTDIR}/boot/loader.conf 123 124 # Disable KbdInteractiveAuthentication according to EC2 requirements. 125 sed -i '' -e \ 126 's/^#KbdInteractiveAuthentication yes/KbdInteractiveAuthentication no/' \ 127 ${DESTDIR}/etc/ssh/sshd_config 128 129 # Use FreeBSD Update and Portsnap mirrors hosted in AWS 130 sed -i '' -e 's/update.FreeBSD.org/aws.update.FreeBSD.org/' \ 131 ${DESTDIR}/etc/freebsd-update.conf 132 sed -i '' -e 's/portsnap.FreeBSD.org/aws.portsnap.FreeBSD.org/' \ 133 ${DESTDIR}/etc/portsnap.conf 134 135 # Use the NTP service provided by Amazon 136 sed -i '' -e 's/^pool/#pool/' \ 137 -e '1,/^#server/s/^#server.*/server 169.254.169.123 iburst/' \ 138 ${DESTDIR}/etc/ntp.conf 139 140 # Provide a map for accessing Elastic File System mounts 141 cat > ${DESTDIR}/etc/autofs/special_efs <<'EOF' 142#!/bin/sh 143 144if [ $# -eq 0 ]; then 145 # No way to know which EFS filesystems exist and are 146 # accessible to this EC2 instance. 147 exit 0 148fi 149 150# Provide instructions on how to mount the requested filesystem. 151FS=$1 152REGION=`fetch -qo- http://169.254.169.254/latest/meta-data/placement/availability-zone | sed -e 's/[a-z]$//'` 153echo "-nfsv4,minorversion=1,oneopenown ${FS}.efs.${REGION}.amazonaws.com:/" 154EOF 155 chmod 755 ${DESTDIR}/etc/autofs/special_efs 156 157 # The first time the AMI boots, the installed "first boot" scripts 158 # should be allowed to run: 159 # * ec2_configinit (download and process EC2 user-data) 160 # * ec2_fetchkey (arrange for SSH using the EC2-provided public key) 161 # * growfs (expand the filesystem to fill the provided disk) 162 # * firstboot_freebsd_update (install critical updates) 163 # * firstboot_pkgs (install packages) 164 touch ${DESTDIR}/firstboot 165 166 # Any EC2 ephemeral disks seen when the system first boots will 167 # be "new" disks; there is no "previous boot" when they might have 168 # been seen and used already. 169 touch ${DESTDIR}/var/db/ec2_ephemeral_diskseen 170 171 if ! [ -z "${QEMUSTATIC}" ]; then 172 rm -f ${DESTDIR}/${EMULATOR} 173 fi 174 rm -f ${DESTDIR}/etc/resolv.conf 175 176 return 0 177} 178