├── OSSMETADATA ├── src ├── initrd │ ├── etc │ │ └── systemd │ │ │ ├── network │ │ │ └── all.network │ │ │ └── system │ │ │ ├── multi-user.target.wants │ │ │ ├── watchdoge.service │ │ │ ├── install_from_s3.service │ │ │ └── generate_ssh_keys.service │ │ │ ├── generate_ssh_keys.service │ │ │ ├── watchdoge.service │ │ │ └── install_from_s3.service │ ├── usr │ │ └── local │ │ │ └── bin │ │ │ ├── generate_ssh_host_keys │ │ │ └── install_from_s3 │ └── root │ │ └── kernel.sh ├── grub │ └── grub.cfg ├── configure_bootloader.sh └── add_ssh_key.sh ├── .travis.yml ├── examples └── upload_ami_to_s3.sh ├── README.md └── LICENSE /OSSMETADATA: -------------------------------------------------------------------------------- 1 | osslifecycle=maintenance 2 | -------------------------------------------------------------------------------- /src/initrd/etc/systemd/network/all.network: -------------------------------------------------------------------------------- 1 | [Network] 2 | DHCP=yes 3 | -------------------------------------------------------------------------------- /src/initrd/etc/systemd/system/multi-user.target.wants/watchdoge.service: -------------------------------------------------------------------------------- 1 | ../watchdoge.service -------------------------------------------------------------------------------- /src/grub/grub.cfg: -------------------------------------------------------------------------------- 1 | linux /boot/vmlinuz console=ttyS0 root= 2 | initrd /boot/initrd.gz 3 | boot 4 | -------------------------------------------------------------------------------- /src/initrd/etc/systemd/system/multi-user.target.wants/install_from_s3.service: -------------------------------------------------------------------------------- 1 | ../install_from_s3.service -------------------------------------------------------------------------------- /src/initrd/etc/systemd/system/multi-user.target.wants/generate_ssh_keys.service: -------------------------------------------------------------------------------- 1 | ../generate_ssh_keys.service -------------------------------------------------------------------------------- /src/initrd/etc/systemd/system/generate_ssh_keys.service: -------------------------------------------------------------------------------- 1 | [Unit] 2 | Description=Generate SSH keys 3 | Before=ssh.service 4 | 5 | [Service] 6 | Type=oneshot 7 | ExecStart=/usr/local/bin/generate_ssh_host_keys 8 | -------------------------------------------------------------------------------- /src/initrd/etc/systemd/system/watchdoge.service: -------------------------------------------------------------------------------- 1 | [Unit] 2 | Description=Watchdoge that reboots when up too long 3 | After=network-online.target 4 | Wants=network-online.target 5 | 6 | [Service] 7 | ExecStart=/usr/local/bin/watchdoge 8 | StandardOutput=journal+console 9 | -------------------------------------------------------------------------------- /src/initrd/etc/systemd/system/install_from_s3.service: -------------------------------------------------------------------------------- 1 | [Unit] 2 | Description=Install an image from S3 3 | After=network-online.target 4 | Wants=network-online.target 5 | 6 | [Service] 7 | ExecStart=/usr/local/bin/install_from_s3 8 | Restart=always 9 | RestartSec=20 10 | StandardOutput=journal+console 11 | -------------------------------------------------------------------------------- /src/configure_bootloader.sh: -------------------------------------------------------------------------------- 1 | #!/bin/bash 2 | set -o errexit 3 | set -o nounset 4 | set -o pipefail 5 | 6 | if [[ -z ${2:-} ]]; then 7 | cat >&2 << EOF 8 | Usage: $0 9 | Configures the in-memory OS to flash the specified S3 key onto the specified 10 | root device 11 | EOF 12 | fi 13 | 14 | s3_image="$1" 15 | shift 16 | root_device="$1" 17 | 18 | sed -ie "s#root=.*#root=${root_device} source=${s3_image}#" /boot/grub/grub.cfg 19 | -------------------------------------------------------------------------------- /src/add_ssh_key.sh: -------------------------------------------------------------------------------- 1 | #!/bin/bash 2 | set -o errexit 3 | set -o nounset 4 | set -o pipefail 5 | 6 | if [[ -z "${1:-}" || ! -e initrd.gz ]]; then 7 | cat >&2 < 9 | run this script in the same directory as the initrd.gz you would like to modify 10 | EOF 11 | exit 1 12 | fi 13 | 14 | readonly initrd_dir="${PWD}" 15 | readonly source_file="${1}" 16 | readonly authkeys="root/.ssh/authorized_keys" 17 | 18 | TEMPDIR=$(mktemp -d) 19 | mkdir -p "${TEMPDIR}/root/.ssh" 20 | cp "${source_file}" "${TEMPDIR}/${authkeys}" 21 | cd "${TEMPDIR}" 22 | 23 | # Be careful not to include / in the new archive 24 | # If one does, systemd-networkd will not come up, due to a permission issue. 25 | find ./* -print0 | cpio -o -H newc -R 0:0 --null 2>/dev/null | gzip >> "${initrd_dir}/initrd.gz" 26 | rm -rf "${TEMPDIR}" 27 | -------------------------------------------------------------------------------- /src/initrd/usr/local/bin/generate_ssh_host_keys: -------------------------------------------------------------------------------- 1 | #!/bin/bash 2 | # 3 | # Copyright 2019 Netflix, Inc. 4 | # 5 | # Licensed under the Apache License, Version 2.0 (the "License"); 6 | # you may not use this file except in compliance with the License. 7 | # You may obtain a copy of the License at 8 | # 9 | # http://www.apache.org/licenses/LICENSE-2.0 10 | # 11 | # Unless required by applicable law or agreed to in writing, software 12 | # distributed under the License is distributed on an "AS IS" BASIS, 13 | # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 | # See the License for the specific language governing permissions and 15 | # limitations under the License. 16 | 17 | ssh-keygen -q -f /etc/ssh/ssh_host_rsa_key -N '' -t rsa 18 | ssh-keygen -q -f /etc/ssh/ssh_host_dsa_key -N '' -t dsa 19 | ssh-keygen -q -f /etc/ssh/ssh_host_ecdsa_key -N '' -t ecdsa 20 | ssh-keygen -q -f /etc/ssh/ssh_host_ed25519_key -N '' -t ed25519 21 | -------------------------------------------------------------------------------- /.travis.yml: -------------------------------------------------------------------------------- 1 | language: minimal 2 | dist: bionic 3 | script: sudo ./build.sh 4 | deploy: 5 | provider: releases 6 | api_key: 7 | secure: 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 8 | file: build/bootloader-*.tar.gz 9 | file_glob: true 10 | draft: true 11 | on: 12 | repo: Netflix-Skunkworks/s3-flash-bootloader 13 | -------------------------------------------------------------------------------- /src/initrd/root/kernel.sh: -------------------------------------------------------------------------------- 1 | #!/bin/bash 2 | # 3 | # Copyright 2019 Netflix, Inc. 4 | # 5 | # Licensed under the Apache License, Version 2.0 (the "License"); 6 | # you may not use this file except in compliance with the License. 7 | # You may obtain a copy of the License at 8 | # 9 | # http://www.apache.org/licenses/LICENSE-2.0 10 | # 11 | # Unless required by applicable law or agreed to in writing, software 12 | # distributed under the License is distributed on an "AS IS" BASIS, 13 | # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 | # See the License for the specific language governing permissions and 15 | # limitations under the License. 16 | 17 | set -x 18 | set -o errexit 19 | set -o nounset 20 | set -o pipefail 21 | 22 | KERNEL_VERSION="${1}" 23 | 24 | cd /root 25 | apt-get update 26 | apt-get install --no-install-recommends -y liblz4-tool awscli curl "linux-modules-${KERNEL_VERSION}" 27 | apt-get download "linux-image-${KERNEL_VERSION}" 28 | dpkg -x *.deb / 29 | depmod "${KERNEL_VERSION}" 30 | systemctl enable systemd-networkd.service 31 | systemctl enable systemd-resolved.service 32 | systemctl enable systemd-networkd-wait-online.service 33 | rm -r /etc/systemd/system/getty.target.wants 34 | sed -ie 's/^root:\*:/root::/' /etc/shadow 35 | -------------------------------------------------------------------------------- /src/initrd/usr/local/bin/install_from_s3: -------------------------------------------------------------------------------- 1 | #!/bin/bash -x 2 | # 3 | # Copyright 2019 Netflix, Inc. 4 | # 5 | # Licensed under the Apache License, Version 2.0 (the "License"); 6 | # you may not use this file except in compliance with the License. 7 | # You may obtain a copy of the License at 8 | # 9 | # http://www.apache.org/licenses/LICENSE-2.0 10 | # 11 | # Unless required by applicable law or agreed to in writing, software 12 | # distributed under the License is distributed on an "AS IS" BASIS, 13 | # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 | # See the License for the specific language governing permissions and 15 | # limitations under the License. 16 | 17 | set -o errexit 18 | set -o nounset 19 | set -o pipefail 20 | 21 | function watchdoge { 22 | sleep 1000 23 | exec 3> /root/watchdoge.lock 24 | # Don't try to restart if the flock is held 25 | flock -n 3 26 | echo "watchdoge restoring original OS" 27 | mount "${root}" /mnt 28 | cd /mnt 29 | rm -r boot 30 | mv boot.bak boot 31 | } 32 | 33 | function s3_install { 34 | modprobe nvme 35 | 36 | read -a cmdline < /proc/cmdline 37 | 38 | for arg in "${cmdline[@]}"; do 39 | case "${arg}" in 40 | root=UUID=*) 41 | root="/dev/disk/by-uuid/${arg#root=UUID=}" 42 | ;; 43 | root=*) 44 | root="${arg#root=}" 45 | ;; 46 | source=*) 47 | source_file="${arg#source=}" 48 | ;; 49 | esac 50 | done 51 | 52 | ls -lR /root 53 | echo "Root: ${root}" 54 | echo "Source: s3://${source_file}" 55 | 56 | aws s3 cp "s3://${source_file}" /root/image.lz4 57 | 58 | # Infinite loop; will be interrupted by watchdog if the disk never arrives 59 | while ! test -e "${root}"; do sleep 0.1; done 60 | 61 | # Take the watchdoge lock, to prevent the watchdoge from rebooting us. 62 | flock -n 3 63 | lz4 -d "/root/image.lz4" > "${root}" 64 | } 65 | 66 | exec 3> /root/watchdoge.lock 67 | 68 | case "${0##*/}" in 69 | watchdoge) 70 | watchdoge 71 | ;; 72 | *) 73 | s3_install 74 | ;; 75 | esac 76 | 77 | exec reboot -f 78 | -------------------------------------------------------------------------------- /examples/upload_ami_to_s3.sh: -------------------------------------------------------------------------------- 1 | #!/bin/bash 2 | # 3 | # Copyright 2019 Netflix, Inc. 4 | # 5 | # Licensed under the Apache License, Version 2.0 (the "License"); 6 | # you may not use this file except in compliance with the License. 7 | # You may obtain a copy of the License at 8 | # 9 | # http://www.apache.org/licenses/LICENSE-2.0 10 | # 11 | # Unless required by applicable law or agreed to in writing, software 12 | # distributed under the License is distributed on an "AS IS" BASIS, 13 | # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 | # See the License for the specific language governing permissions and 15 | # limitations under the License. 16 | 17 | set -o errexit 18 | set -o nounset 19 | set -o pipefail 20 | 21 | if [[ -z ${2:-} ]]; then 22 | cat >&2 < 24 | Copies an EBS-backed AMI image to S3 as an lz4-compressed blob 25 | EOF 26 | exit 1 27 | fi 28 | 29 | readonly ami_id="$1" 30 | shift 31 | readonly s3_url="$1" 32 | 33 | readonly device_name="/dev/xvdg" 34 | 35 | cat >&2 </ /dev/disk/by-label/cloudimg-rootfs 56 | # Add a SSH key so that you can access the bootloader while it is running 57 | /boot/add_ssh_key.sh ~/.ssh/id_ed25519.pub 58 | 59 | [release]: https://github.com/Netflix-Skunkworks/s3-flash-bootloader/releases/latest/download/bootloader-x86_64.tar.gz 60 | 61 | # Producing flashable images 62 | 63 | s3-flash-bootloader requires lz4-compressed full disk images stored in s3. 64 | Included in the examples directory of this repo is a script to upload the 65 | contents of an AMI to S3. We hope this script can serve as a useful template as 66 | you adapt it to fit your environment. At Netflix we tie similar automation into 67 | our AMI baking piplines which upload the disk image directly to S3 in addition 68 | to the normal snapshot and publish. 69 | 70 | # Usage note 71 | 72 | Most stateful services depend on caches to achieve good performance. After a 73 | system is rebooted, it is likely that these caches will be cold, and unable to 74 | offer appropriate performance. We recommend re-warming caches before applying 75 | traffic to any rebooted stateful service. 76 | 77 | * within Netflix, we use [happycache][happycache], which works for databases 78 | that use the Linux page cache (e.g. Cassandra, Postgres) 79 | * [pgfadvise_loader][pgfincore] is available as an extension to Postgres 80 | * MySQL can [dump and reload][mysql-preload] its buffer pool 81 | 82 | [happycache]: https://github.com/hashbrowncipher/happycache 83 | [pgfincore]: https://git.postgresql.org/gitweb/?p=pgfincore.git;a=blob;f=README.md;h=e72215ec2cda0fa0b8fc0930f55588f1e09c64d6;hb=refs/heads/master 84 | [mysql-preload]: https://dev.mysql.com/doc/refman/5.6/en/innodb-preload-buffer-pool.html 85 | 86 | # Similar software 87 | 88 | Many operating systems have built-in mechanisms for performing in-place 89 | upgrades using full images, including most network-device OSes, Chromebooks, 90 | and container OSes like Container Linux. s3-flash-bootloader uses similar 91 | mechanisms, but intentionally does not require any integration with the OS 92 | being booted. As a result, we are compatible with any OS image. 93 | 94 | # Building 95 | 96 | You may also build from source by cloning this repository and running 97 | `./build.sh`. The build process uses debootstrap, and generally assumes a 98 | Debian-like OS. 99 | 100 | # Contributing 101 | 102 | We hope this code is useful for you, and we are happy to accept bugfixes. 103 | If you prefer to build new features we encourage you to fork and adapt this to 104 | your needs. 105 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | Apache License 2 | Version 2.0, January 2004 3 | http://www.apache.org/licenses/ 4 | 5 | TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 6 | 7 | 1. Definitions. 8 | 9 | "License" shall mean the terms and conditions for use, reproduction, 10 | and distribution as defined by Sections 1 through 9 of this document. 11 | 12 | "Licensor" shall mean the copyright owner or entity authorized by 13 | the copyright owner that is granting the License. 14 | 15 | "Legal Entity" shall mean the union of the acting entity and all 16 | other entities that control, are controlled by, or are under common 17 | control with that entity. For the purposes of this definition, 18 | "control" means (i) the power, direct or indirect, to cause the 19 | direction or management of such entity, whether by contract or 20 | otherwise, or (ii) ownership of fifty percent (50%) or more of the 21 | outstanding shares, or (iii) beneficial ownership of such entity. 22 | 23 | "You" (or "Your") shall mean an individual or Legal Entity 24 | exercising permissions granted by this License. 25 | 26 | "Source" form shall mean the preferred form for making modifications, 27 | including but not limited to software source code, documentation 28 | source, and configuration files. 29 | 30 | "Object" form shall mean any form resulting from mechanical 31 | transformation or translation of a Source form, including but 32 | not limited to compiled object code, generated documentation, 33 | and conversions to other media types. 34 | 35 | "Work" shall mean the work of authorship, whether in Source or 36 | Object form, made available under the License, as indicated by a 37 | copyright notice that is included in or attached to the work 38 | (an example is provided in the Appendix below). 39 | 40 | "Derivative Works" shall mean any work, whether in Source or Object 41 | form, that is based on (or derived from) the Work and for which the 42 | editorial revisions, annotations, elaborations, or other modifications 43 | represent, as a whole, an original work of authorship. For the purposes 44 | of this License, Derivative Works shall not include works that remain 45 | separable from, or merely link (or bind by name) to the interfaces of, 46 | the Work and Derivative Works thereof. 47 | 48 | "Contribution" shall mean any work of authorship, including 49 | the original version of the Work and any modifications or additions 50 | to that Work or Derivative Works thereof, that is intentionally 51 | submitted to Licensor for inclusion in the Work by the copyright owner 52 | or by an individual or Legal Entity authorized to submit on behalf of 53 | the copyright owner. For the purposes of this definition, "submitted" 54 | means any form of electronic, verbal, or written communication sent 55 | to the Licensor or its representatives, including but not limited to 56 | communication on electronic mailing lists, source code control systems, 57 | and issue tracking systems that are managed by, or on behalf of, the 58 | Licensor for the purpose of discussing and improving the Work, but 59 | excluding communication that is conspicuously marked or otherwise 60 | designated in writing by the copyright owner as "Not a Contribution." 61 | 62 | "Contributor" shall mean Licensor and any individual or Legal Entity 63 | on behalf of whom a Contribution has been received by Licensor and 64 | subsequently incorporated within the Work. 65 | 66 | 2. Grant of Copyright License. Subject to the terms and conditions of 67 | this License, each Contributor hereby grants to You a perpetual, 68 | worldwide, non-exclusive, no-charge, royalty-free, irrevocable 69 | copyright license to reproduce, prepare Derivative Works of, 70 | publicly display, publicly perform, sublicense, and distribute the 71 | Work and such Derivative Works in Source or Object form. 72 | 73 | 3. Grant of Patent License. Subject to the terms and conditions of 74 | this License, each Contributor hereby grants to You a perpetual, 75 | worldwide, non-exclusive, no-charge, royalty-free, irrevocable 76 | (except as stated in this section) patent license to make, have made, 77 | use, offer to sell, sell, import, and otherwise transfer the Work, 78 | where such license applies only to those patent claims licensable 79 | by such Contributor that are necessarily infringed by their 80 | Contribution(s) alone or by combination of their Contribution(s) 81 | with the Work to which such Contribution(s) was submitted. If You 82 | institute patent litigation against any entity (including a 83 | cross-claim or counterclaim in a lawsuit) alleging that the Work 84 | or a Contribution incorporated within the Work constitutes direct 85 | or contributory patent infringement, then any patent licenses 86 | granted to You under this License for that Work shall terminate 87 | as of the date such litigation is filed. 88 | 89 | 4. Redistribution. You may reproduce and distribute copies of the 90 | Work or Derivative Works thereof in any medium, with or without 91 | modifications, and in Source or Object form, provided that You 92 | meet the following conditions: 93 | 94 | (a) You must give any other recipients of the Work or 95 | Derivative Works a copy of this License; and 96 | 97 | (b) You must cause any modified files to carry prominent notices 98 | stating that You changed the files; and 99 | 100 | (c) You must retain, in the Source form of any Derivative Works 101 | that You distribute, all copyright, patent, trademark, and 102 | attribution notices from the Source form of the Work, 103 | excluding those notices that do not pertain to any part of 104 | the Derivative Works; and 105 | 106 | (d) If the Work includes a "NOTICE" text file as part of its 107 | distribution, then any Derivative Works that You distribute must 108 | include a readable copy of the attribution notices contained 109 | within such NOTICE file, excluding those notices that do not 110 | pertain to any part of the Derivative Works, in at least one 111 | of the following places: within a NOTICE text file distributed 112 | as part of the Derivative Works; within the Source form or 113 | documentation, if provided along with the Derivative Works; or, 114 | within a display generated by the Derivative Works, if and 115 | wherever such third-party notices normally appear. The contents 116 | of the NOTICE file are for informational purposes only and 117 | do not modify the License. You may add Your own attribution 118 | notices within Derivative Works that You distribute, alongside 119 | or as an addendum to the NOTICE text from the Work, provided 120 | that such additional attribution notices cannot be construed 121 | as modifying the License. 122 | 123 | You may add Your own copyright statement to Your modifications and 124 | may provide additional or different license terms and conditions 125 | for use, reproduction, or distribution of Your modifications, or 126 | for any such Derivative Works as a whole, provided Your use, 127 | reproduction, and distribution of the Work otherwise complies with 128 | the conditions stated in this License. 129 | 130 | 5. Submission of Contributions. Unless You explicitly state otherwise, 131 | any Contribution intentionally submitted for inclusion in the Work 132 | by You to the Licensor shall be under the terms and conditions of 133 | this License, without any additional terms or conditions. 134 | Notwithstanding the above, nothing herein shall supersede or modify 135 | the terms of any separate license agreement you may have executed 136 | with Licensor regarding such Contributions. 137 | 138 | 6. Trademarks. This License does not grant permission to use the trade 139 | names, trademarks, service marks, or product names of the Licensor, 140 | except as required for reasonable and customary use in describing the 141 | origin of the Work and reproducing the content of the NOTICE file. 142 | 143 | 7. Disclaimer of Warranty. Unless required by applicable law or 144 | agreed to in writing, Licensor provides the Work (and each 145 | Contributor provides its Contributions) on an "AS IS" BASIS, 146 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or 147 | implied, including, without limitation, any warranties or conditions 148 | of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A 149 | PARTICULAR PURPOSE. You are solely responsible for determining the 150 | appropriateness of using or redistributing the Work and assume any 151 | risks associated with Your exercise of permissions under this License. 152 | 153 | 8. Limitation of Liability. In no event and under no legal theory, 154 | whether in tort (including negligence), contract, or otherwise, 155 | unless required by applicable law (such as deliberate and grossly 156 | negligent acts) or agreed to in writing, shall any Contributor be 157 | liable to You for damages, including any direct, indirect, special, 158 | incidental, or consequential damages of any character arising as a 159 | result of this License or out of the use or inability to use the 160 | Work (including but not limited to damages for loss of goodwill, 161 | work stoppage, computer failure or malfunction, or any and all 162 | other commercial damages or losses), even if such Contributor 163 | has been advised of the possibility of such damages. 164 | 165 | 9. Accepting Warranty or Additional Liability. While redistributing 166 | the Work or Derivative Works thereof, You may choose to offer, 167 | and charge a fee for, acceptance of support, warranty, indemnity, 168 | or other liability obligations and/or rights consistent with this 169 | License. However, in accepting such obligations, You may act only 170 | on Your own behalf and on Your sole responsibility, not on behalf 171 | of any other Contributor, and only if You agree to indemnify, 172 | defend, and hold each Contributor harmless for any liability 173 | incurred by, or claims asserted against, such Contributor by reason 174 | of your accepting any such warranty or additional liability. 175 | 176 | END OF TERMS AND CONDITIONS 177 | 178 | APPENDIX: How to apply the Apache License to your work. 179 | 180 | To apply the Apache License to your work, attach the following 181 | boilerplate notice, with the fields enclosed by brackets "[]" 182 | replaced with your own identifying information. (Don't include 183 | the brackets!) The text should be enclosed in the appropriate 184 | comment syntax for the file format. We also recommend that a 185 | file or class name and description of purpose be included on the 186 | same "printed page" as the copyright notice for easier 187 | identification within third-party archives. 188 | 189 | Copyright 2019 Netflix, Inc. 190 | 191 | Licensed under the Apache License, Version 2.0 (the "License"); 192 | you may not use this file except in compliance with the License. 193 | You may obtain a copy of the License at 194 | 195 | http://www.apache.org/licenses/LICENSE-2.0 196 | 197 | Unless required by applicable law or agreed to in writing, software 198 | distributed under the License is distributed on an "AS IS" BASIS, 199 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 200 | See the License for the specific language governing permissions and 201 | limitations under the License. 202 | --------------------------------------------------------------------------------