xref: /freebsd/release/tools/ec2.conf (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
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