├── CODE_OF_CONDUCT.md ├── CONTRIBUTORS ├── Dockerfile ├── LICENSE ├── README.md ├── assets └── startup.sh ├── build-multiarch.sh ├── build.sh ├── docker-compose.yml ├── run.sh └── vars /CODE_OF_CONDUCT.md: -------------------------------------------------------------------------------- 1 | # Contributor Covenant Code of Conduct 2 | 3 | ## Our Pledge 4 | 5 | In the interest of fostering an open and welcoming environment, we as 6 | contributors and maintainers pledge to making participation in our project and 7 | our community a harassment-free experience for everyone, regardless of age, body 8 | size, disability, ethnicity, sex characteristics, gender identity and expression, 9 | level of experience, education, socio-economic status, nationality, personal 10 | appearance, race, religion, or sexual identity and orientation. 11 | 12 | ## Our Standards 13 | 14 | Examples of behavior that contributes to creating a positive environment 15 | include: 16 | 17 | * Using welcoming and inclusive language 18 | * Being respectful of differing viewpoints and experiences 19 | * Gracefully accepting constructive criticism 20 | * Focusing on what is best for the community 21 | * Showing empathy towards other community members 22 | 23 | Examples of unacceptable behavior by participants include: 24 | 25 | * The use of sexualized language or imagery and unwelcome sexual attention or 26 | advances 27 | * Trolling, insulting/derogatory comments, and personal or political attacks 28 | * Public or private harassment 29 | * Publishing others' private information, such as a physical or electronic 30 | address, without explicit permission 31 | * Other conduct which could reasonably be considered inappropriate in a 32 | professional setting 33 | 34 | ## Our Responsibilities 35 | 36 | Project maintainers are responsible for clarifying the standards of acceptable 37 | behavior and are expected to take appropriate and fair corrective action in 38 | response to any instances of unacceptable behavior. 39 | 40 | Project maintainers have the right and responsibility to remove, edit, or 41 | reject comments, commits, code, wiki edits, issues, and other contributions 42 | that are not aligned to this Code of Conduct, or to ban temporarily or 43 | permanently any contributor for other behaviors that they deem inappropriate, 44 | threatening, offensive, or harmful. 45 | 46 | ## Scope 47 | 48 | This Code of Conduct applies both within project spaces and in public spaces 49 | when an individual is representing the project or its community. Examples of 50 | representing a project or community include using an official project e-mail 51 | address, posting via an official social media account, or acting as an appointed 52 | representative at an online or offline event. Representation of a project may be 53 | further defined and clarified by project maintainers. 54 | 55 | ## Enforcement 56 | 57 | Instances of abusive, harassing, or otherwise unacceptable behavior may be 58 | reported by contacting the project team at cturra@gmail.com. All 59 | complaints will be reviewed and investigated and will result in a response that 60 | is deemed necessary and appropriate to the circumstances. The project team is 61 | obligated to maintain confidentiality with regard to the reporter of an incident. 62 | Further details of specific enforcement policies may be posted separately. 63 | 64 | Project maintainers who do not follow or enforce the Code of Conduct in good 65 | faith may face temporary or permanent repercussions as determined by other 66 | members of the project's leadership. 67 | 68 | ## Attribution 69 | 70 | This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4, 71 | available at https://www.contributor-covenant.org/version/1/4/code-of-conduct.html 72 | 73 | [homepage]: https://www.contributor-covenant.org 74 | 75 | For answers to common questions about this code of conduct, see 76 | https://www.contributor-covenant.org/faq 77 | -------------------------------------------------------------------------------- /CONTRIBUTORS: -------------------------------------------------------------------------------- 1 | The following awesome folks have contributed ideas, 2 | bug reports and code to this ntp docker project: 3 | 4 | - Chris Turra => https://github.com/cturra 5 | - Clément Péron => https://github.com/clementperon 6 | - Fabian Wünderich => https://github.com/fanonwue 7 | - Fakuivan => https://github.com/fakuivan 8 | - Gontier-Julien => https://github.com/Gontier-Julien 9 | - Guru Govindan => https://github.com/ggovindan 10 | - Kim Oliver Drechsel => https://github.com/kimdre 11 | - Nicolas Carrier => https://github.com/ncarrier 12 | - Nicolas Innocenti => https://github.com/nicoinn 13 | - Richard Coleman => https://github.com/microbug 14 | - Simon Rupf => https://github.com/simonrupf 15 | - Trenton H => https://github.com/stumpylog 16 | 17 | 18 | Thanks for your contributions! 19 | -------------------------------------------------------------------------------- /Dockerfile: -------------------------------------------------------------------------------- 1 | FROM alpine:latest 2 | 3 | ARG BUILD_DATE 4 | 5 | # first, a bit about this container 6 | LABEL build_info="cturra/docker-ntp build-date:- ${BUILD_DATE}" 7 | LABEL maintainer="Chris Turra " 8 | LABEL documentation="https://github.com/cturra/docker-ntp" 9 | 10 | # install chrony 11 | RUN apk add --no-cache chrony tzdata 12 | 13 | # script to configure/startup chrony (ntp) 14 | COPY assets/startup.sh /opt/startup.sh 15 | 16 | # ntp port 17 | EXPOSE 123/udp 18 | 19 | # let docker know how to test container health 20 | HEALTHCHECK CMD chronyc -n tracking || exit 1 21 | 22 | # start chronyd in the foreground 23 | ENTRYPOINT [ "/bin/sh", "/opt/startup.sh" ] 24 | -------------------------------------------------------------------------------- /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. 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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 2017 Chris Turra (cturra) 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 | 203 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | ## About this container 2 | 3 | [![Docker Pulls](https://img.shields.io/docker/pulls/cturra/ntp.svg?logo=docker&label=pulls&style=for-the-badge&color=0099ff&logoColor=ffffff)](https://hub.docker.com/r/cturra/ntp/) 4 | [![Docker Stars](https://img.shields.io/docker/stars/cturra/ntp.svg?logo=docker&label=stars&style=for-the-badge&color=0099ff&logoColor=ffffff)](https://hub.docker.com/r/cturra/ntp/) 5 | [![GitHub Stars](https://img.shields.io/github/stars/cturra/docker-ntp.svg?logo=github&label=stars&style=for-the-badge&color=0099ff&logoColor=ffffff)](https://github.com/cturra/docker-ntp) 6 | [![Apache licensed](https://img.shields.io/badge/license-Apache-blue.svg?logo=apache&style=for-the-badge&color=0099ff&logoColor=ffffff)](https://raw.githubusercontent.com/cturra/docker-ntp/master/LICENSE) 7 | 8 | This container runs [chrony](https://chrony-project.org/) on [Alpine Linux](https://alpinelinux.org/). 9 | 10 | [chrony](https://chrony-project.org/) is a versatile implementation of the Network Time Protocol (NTP). It can synchronise the system clock with NTP servers, reference clocks (e.g. GPS receiver), and manual input using wristwatch and keyboard. It can also operate as an NTPv4 (RFC 5905) server and peer to provide a time service to other computers in the network. 11 | 12 | 13 | ## Supported Architectures 14 | 15 | Architectures officially supported by this Docker container. Simply pulling this container from [Docker Hub](https://hub.docker.com/r/cturra/ntp) should retrieve the correct image for your architecture. 16 | 17 | ![Linux x86-64](https://img.shields.io/badge/linux/amd64-green?style=flat-square) 18 | ![ARMv8 64-bit](https://img.shields.io/badge/linux/arm64-green?style=flat-square) 19 | ![IBM POWER8](https://img.shields.io/badge/linux/ppc64le-green?style=flat-square) 20 | ![IBM Z Systems](https://img.shields.io/badge/linux/s390x-green?style=flat-square) 21 | ![Linux x86/i686](https://img.shields.io/badge/linux/386-green?style=flat-squareg) 22 | ![ARMv7 32-bit](https://img.shields.io/badge/linux/arm/v7-green?style=flat-square) 23 | ![ARMv6 32-bit](https://img.shields.io/badge/linux/arm/v6-green?style=flat-square) 24 | 25 | 26 | ## How to Run this container 27 | 28 | ### With the Docker CLI 29 | 30 | Pull and run -- it's this simple. 31 | 32 | ``` 33 | # pull from docker hub 34 | $> docker pull cturra/ntp 35 | 36 | # run ntp 37 | $> docker run --name=ntp \ 38 | --restart=always \ 39 | --detach \ 40 | --publish=123:123/udp \ 41 | cturra/ntp 42 | 43 | # OR run ntp with higher security 44 | $> docker run --name=ntp \ 45 | --restart=always \ 46 | --detach \ 47 | --publish=123:123/udp \ 48 | --read-only \ 49 | --tmpfs=/etc/chrony:rw,mode=1750 \ 50 | --tmpfs=/run/chrony:rw,mode=1750 \ 51 | --tmpfs=/var/lib/chrony:rw,mode=1750 \ 52 | cturra/ntp 53 | ``` 54 | 55 | 56 | ### With Docker Compose 57 | 58 | Using the docker-compose.yml file included in this git repo, you can build the container yourself (should you choose to). 59 | *Note: this docker-compose files uses the `3.9` compose format, which requires Docker Engine release 19.03.0+ 60 | 61 | ``` 62 | # run ntp 63 | $> docker compose up -d ntp 64 | 65 | # (optional) check the ntp logs 66 | $> docker compose logs ntp 67 | ``` 68 | 69 | 70 | ### With Docker Swarm 71 | 72 | *(These instructions assume you already have a swarm)* 73 | 74 | ``` 75 | # deploy ntp stack to the swarm 76 | $> docker stack deploy -c docker-compose.yml cturra 77 | 78 | # check that service is running 79 | $> docker stack services cturra 80 | 81 | # (optional) view the ntp logs 82 | $> docker service logs -f cturra_ntp 83 | ``` 84 | 85 | 86 | ### From a Local command line 87 | 88 | Using the vars file in this git repo, you can update any of the variables to reflect your 89 | environment. Once updated, simply execute the build then run scripts. 90 | 91 | ``` 92 | # build ntp 93 | $> ./build.sh 94 | 95 | # run ntp 96 | $> ./run.sh 97 | ``` 98 | 99 | 100 | ## Configure NTP Servers 101 | 102 | By default, this container uses CloudFlare's time server (time.cloudflare.com). If you'd 103 | like to use one or more different NTP server(s), you can pass this container an `NTP_SERVERS` 104 | environment variable. This can be done by updating the [vars](vars), [docker-compose.yml](docker-compose.yml) 105 | files or manually passing `--env=NTP_SERVERS="..."` to `docker run`. 106 | 107 | Below are some examples of how to configure common NTP Servers. 108 | 109 | Do note, to configure more than one server, you must use a comma delimited list WITHOUT spaces. 110 | 111 | ``` 112 | # (default) cloudflare 113 | NTP_SERVERS="time.cloudflare.com" 114 | 115 | # google 116 | NTP_SERVERS="time1.google.com,time2.google.com,time3.google.com,time4.google.com" 117 | 118 | # alibaba 119 | NTP_SERVERS="ntp1.aliyun.com,ntp2.aliyun.com,ntp3.aliyun.com,ntp4.aliyun.com" 120 | 121 | # local (offline) 122 | NTP_SERVERS="127.127.1.1" 123 | ``` 124 | 125 | If you're interested in a public list of stratum 1 servers, you can have a look at the following list. 126 | Do make sure to verify the ntp server is active as this list does appaer to have some no longer active 127 | servers. 128 | 129 | * https://www.advtimesync.com/docs/manual/stratum1.html 130 | 131 | 132 | ## Chronyd Options 133 | 134 | ### No Client Log (noclientlog) 135 | 136 | This is optional and not enabled by default. If you provide the `NOCLIENTLOG=true` envivonrment variable, 137 | chrony will be configured to: 138 | 139 | > Specifies that client accesses are not to be logged. Normally they are logged, allowing statistics to 140 | > be reported using the clients command in chronyc. This option also effectively disables server support 141 | > for the NTP interleaved mode. 142 | 143 | 144 | ## Logging 145 | 146 | By default, this project logs informational messages to stdout, which can be helpful when running the 147 | ntp service. If you'd like to change the level of log verbosity, pass the `LOG_LEVEL` environment 148 | variable to the container, specifying the level (`#`) when you first start it. This option matches 149 | the chrony `-L` option, which support the following levels can to specified: 0 (informational), 1 150 | (warning), 2 (non-fatal error), and 3 (fatal error). 151 | 152 | Feel free to check out the project documentation for more information at: 153 | 154 | * https://chrony-project.org/documentation.html 155 | 156 | 157 | ## Setting your timezone 158 | 159 | By default the UTC timezone is used, however if you'd like to adjust your NTP server to be running in your 160 | local timezone, all you need to do is provide a `TZ` environment variable following the standard TZ data format. 161 | As an example, using `docker-compose.yaml`, that would look like this if you were located in Vancouver, Canada: 162 | 163 | ```yaml 164 | ... 165 | environment: 166 | - TZ=America/Vancouver 167 | ... 168 | ``` 169 | 170 | 171 | ## Enable Network Time Security 172 | 173 | If **all** the `NTP_SERVERS` you have configured support NTS (Network Time Security) you can pass the `ENABLE_NTS=true` 174 | option to the container to enable it. As an example, using `docker-compose.yaml`, that would look like this: 175 | 176 | ```yaml 177 | ... 178 | environment: 179 | - NTP_SERVERS=time.cloudflare.com 180 | - ENABLE_NTS=true 181 | ... 182 | ``` 183 | 184 | If any of the `NTP_SERVERS` you have configured does not support NTS, you will see a message like the 185 | following during startup: 186 | 187 | > NTS-KE session with 164.67.62.194:4460 (tick.ucla.edu) timed out 188 | 189 | 190 | ## Testing your NTP Container 191 | 192 | From any machine that has `ntpdate` you can query your new NTP container with the follow 193 | command: 194 | 195 | ``` 196 | $> ntpdate -q 197 | ``` 198 | 199 | 200 | Here is a sample output from my environment: 201 | 202 | ``` 203 | $> ntpdate -q 10.13.13.9 204 | server 10.13.1.109, stratum 4, offset 0.000642, delay 0.02805 205 | 14 Mar 19:21:29 ntpdate[26834]: adjust time server 10.13.13.109 offset 0.000642 sec 206 | ``` 207 | 208 | 209 | If you see a message, like the following, it's likely the clock is not yet synchronized. 210 | You should see this go away if you wait a bit longer and query again. 211 | ``` 212 | $> ntpdate -q 10.13.13.9 213 | server 10.13.13.9, stratum 16, offset 0.005689, delay 0.02837 214 | 11 Dec 09:47:53 ntpdate[26030]: no server suitable for synchronization found 215 | ``` 216 | 217 | To see details on the ntp status of your container, you can check with the command below 218 | on your docker host: 219 | ``` 220 | $> docker exec ntp chronyc tracking 221 | Reference ID : D8EF2300 (time1.google.com) 222 | Stratum : 2 223 | Ref time (UTC) : Sun Mar 15 04:33:30 2020 224 | System time : 0.000054161 seconds slow of NTP time 225 | Last offset : -0.000015060 seconds 226 | RMS offset : 0.000206534 seconds 227 | Frequency : 5.626 ppm fast 228 | Residual freq : -0.001 ppm 229 | Skew : 0.118 ppm 230 | Root delay : 0.022015510 seconds 231 | Root dispersion : 0.001476757 seconds 232 | Update interval : 1025.2 seconds 233 | Leap status : Normal 234 | ``` 235 | 236 | 237 | Here is how you can see a peer list to verify the state of each ntp source configured: 238 | ``` 239 | $> docker exec ntp chronyc sources 240 | 210 Number of sources = 2 241 | MS Name/IP address Stratum Poll Reach LastRx Last sample 242 | =============================================================================== 243 | ^+ time.cloudflare.com 3 10 377 404 -623us[ -623us] +/- 24ms 244 | ^* time1.google.com 1 10 377 1023 +259us[ +244us] +/- 11ms 245 | ``` 246 | 247 | 248 | Finally, if you'd like to see statistics about the collected measurements of each ntp 249 | source configured: 250 | ``` 251 | $> docker exec ntp chronyc sourcestats 252 | 210 Number of sources = 2 253 | Name/IP Address NP NR Span Frequency Freq Skew Offset Std Dev 254 | ============================================================================== 255 | time.cloudflare.com 35 18 139m +0.014 0.141 -662us 530us 256 | time1.google.com 33 13 128m -0.007 0.138 +318us 460us 257 | ``` 258 | 259 | 260 | Are you seeing messages like these and wondering what is going on? 261 | ``` 262 | $ docker logs -f ntps 263 | [...] 264 | 2021-05-25T18:41:40Z System clock wrong by -2.535004 seconds 265 | 2021-05-25T18:41:40Z Could not step system clock 266 | 2021-05-25T18:42:47Z System clock wrong by -2.541034 seconds 267 | 2021-05-25T18:42:47Z Could not step system clock 268 | ``` 269 | 270 | Good question! Since `chronyd` is running with the `-x` flag, it will not try to control 271 | the system (container host) clock. This of course is necessary because the process does not 272 | have priviledge (for good reason) to modify the clock on the system. 273 | 274 | Like any host on your network, simply use your preferred ntp client to pull the time from 275 | the running ntp container on your container host. 276 | 277 | --- 278 | Buy Me A Coffee 279 | -------------------------------------------------------------------------------- /assets/startup.sh: -------------------------------------------------------------------------------- 1 | #!/bin/sh 2 | 3 | DEFAULT_NTP="time.cloudflare.com" 4 | CHRONY_CONF_FILE="/etc/chrony/chrony.conf" 5 | 6 | # confirm correct permissions on chrony run directory 7 | if [ -d /run/chrony ]; then 8 | chown -R chrony:chrony /run/chrony 9 | chmod o-rx /run/chrony 10 | # remove previous pid file if it exist 11 | rm -f /var/run/chrony/chronyd.pid 12 | fi 13 | 14 | # confirm correct permissions on chrony variable state directory 15 | if [ -d /var/lib/chrony ]; then 16 | chown -R chrony:chrony /var/lib/chrony 17 | fi 18 | 19 | ## dynamically populate chrony config file. 20 | { 21 | echo "# https://github.com/cturra/docker-ntp" 22 | echo 23 | echo "# chrony.conf file generated by startup script" 24 | echo "# located at /opt/startup.sh" 25 | echo 26 | echo "# time servers provided by NTP_SERVERS environment variables." 27 | } > ${CHRONY_CONF_FILE} 28 | 29 | 30 | # NTP_SERVERS environment variable is not present, so populate with default server 31 | if [ -z "${NTP_SERVERS}" ]; then 32 | NTP_SERVERS="${DEFAULT_NTP}" 33 | fi 34 | 35 | # LOG_LEVEL environment variable is not present, so populate with chrony default (0) 36 | # chrony log levels: 0 (informational), 1 (warning), 2 (non-fatal error) and 3 (fatal error) 37 | if [ -z "${LOG_LEVEL}" ]; then 38 | LOG_LEVEL=0 39 | else 40 | # confirm log level is between 0-3, since these are the only log levels supported 41 | if [ "${LOG_LEVEL}" -gt 3 ]; then 42 | # level outside of supported range, let's set to default (0) 43 | LOG_LEVEL=0 44 | fi 45 | fi 46 | 47 | IFS="," 48 | for N in $NTP_SERVERS; do 49 | # strip any quotes found before or after ntp server 50 | N_CLEANED=${N//\"} 51 | 52 | # check if ntp server has a 127.0.0.0/8 address (RFC3330) indicating it's 53 | # the local system clock 54 | if [[ "${N_CLEANED}" == "127\."* ]]; then 55 | echo "server "${N_CLEANED} >> ${CHRONY_CONF_FILE} 56 | echo "local stratum 10" >> ${CHRONY_CONF_FILE} 57 | 58 | # found external time servers 59 | else 60 | if [[ "${ENABLE_NTS:-false}" = true ]]; then 61 | echo "server "${N_CLEANED}" iburst nts" >> ${CHRONY_CONF_FILE} 62 | else 63 | echo "server "${N_CLEANED}" iburst" >> ${CHRONY_CONF_FILE} 64 | fi 65 | fi 66 | done 67 | 68 | # final bits for the config file 69 | { 70 | echo 71 | echo "driftfile /var/lib/chrony/chrony.drift" 72 | echo "makestep 0.1 3" 73 | if [ "${NOCLIENTLOG:-false}" = true ]; then 74 | echo "noclientlog" 75 | fi 76 | echo 77 | echo "allow all" 78 | } >> ${CHRONY_CONF_FILE} 79 | 80 | ## startup chronyd in the foreground 81 | exec /usr/sbin/chronyd -u chrony -d -x -L ${LOG_LEVEL} 82 | -------------------------------------------------------------------------------- /build-multiarch.sh: -------------------------------------------------------------------------------- 1 | #!/bin/bash 2 | 3 | # grab global variables 4 | source vars 5 | 6 | DOCKER=$(which docker) 7 | BUILD_INST=${CONTAINER_NAME}"-builder" 8 | BUILD_DATE=$(date -u '+%Y-%m-%dT%H:%M:%S%z') 9 | 10 | # MODE options: 11 | # - dry_run: (default) build images, but DO NOT push to dockerhub 12 | # - go_time: build and push all images 13 | MODE="DRY_RUN" 14 | 15 | if [ "$#" -gt 0 ]; then 16 | # argument supplied. check if it's "go time" 17 | if [ "$1" == "--go-time" ]; then 18 | MODE="GO_TIME" 19 | fi 20 | fi 21 | 22 | 23 | ## requirements: 24 | # - docker buildx plugin (https://docs.docker.com/buildx/working-with-buildx/) 25 | if [ ! -f ~/.docker/cli-plugins/docker-buildx ]; then 26 | echo "[ERROR] docker buildx plugin not found!" 27 | echo " => https://github.com/docker/buildx/" 28 | exit 1 29 | 30 | else 31 | # check if build instance (BUILD_INST) is present 32 | BUILDER_CHECK=$($DOCKER buildx ls| grep ${BUILD_INST}) 33 | if [ ! -n "$BUILDER_CHECK" ]; then 34 | # not found. let's create it 35 | $DOCKER run --rm --privileged multiarch/qemu-user-static --reset -p yes 36 | $DOCKER buildx create --name ${BUILD_INST} --driver docker-container --use 37 | fi 38 | 39 | # finally, let's build the ntp container 40 | $DOCKER buildx use ${BUILD_INST} 41 | 42 | # check for dry run. if true, build but do not push image to registry 43 | if [ "${MODE}" == "DRY_RUN" ]; then 44 | $DOCKER buildx build --platform linux/amd64,linux/arm64,linux/ppc64le,linux/s390x,linux/386,linux/arm/v7,linux/arm/v6 \ 45 | --build-arg BUILD_DATE=${BUILD_DATE} \ 46 | --tag ${IMAGE_NAME} . 47 | echo "!! DRY RUN ONLY. NO IMAGE PUSHED TO REGISTRY !!" 48 | 49 | else 50 | $DOCKER buildx build --platform linux/amd64,linux/arm64,linux/ppc64le,linux/s390x,linux/386,linux/arm/v7,linux/arm/v6 \ 51 | --build-arg BUILD_DATE=${BUILD_DATE} \ 52 | --tag ${IMAGE_NAME} \ 53 | --push . 54 | fi 55 | 56 | # clean up build artifacts 57 | $DOCKER rm -f $($DOCKER ps --filter "name=buildx_buildkit" --format "{{.ID}}") 58 | fi 59 | -------------------------------------------------------------------------------- /build.sh: -------------------------------------------------------------------------------- 1 | #!/bin/bash 2 | 3 | # grab global variables 4 | source vars 5 | 6 | DOCKER=$(which docker) 7 | BUILD_DATE=$(date -u '+%Y-%m-%dT%H:%M:%S%z') 8 | 9 | # build image 10 | $DOCKER build --pull \ 11 | --tag ${IMAGE_NAME} \ 12 | --build-arg BUILD_DATE=${BUILD_DATE} \ 13 | . 14 | -------------------------------------------------------------------------------- /docker-compose.yml: -------------------------------------------------------------------------------- 1 | version: '3.9' 2 | 3 | services: 4 | ntp: 5 | build: . 6 | image: cturra/ntp:latest 7 | container_name: ntp 8 | restart: always 9 | ports: 10 | - 123:123/udp 11 | environment: 12 | - NTP_SERVERS=time.cloudflare.com 13 | - LOG_LEVEL=0 14 | # - TZ=America/Vancouver 15 | # - NOCLIENTLOG=true 16 | # - ENABLE_NTS=true 17 | -------------------------------------------------------------------------------- /run.sh: -------------------------------------------------------------------------------- 1 | #!/bin/bash 2 | 3 | # grab global variables 4 | source vars 5 | 6 | DOCKER=$(which docker) 7 | 8 | # function to check if container is running 9 | function check_container() { 10 | $DOCKER ps --filter "name=${CONTAINER_NAME}" --format "{{.ID}}" 11 | } 12 | 13 | # function to start new docker container 14 | function start_container() { 15 | $DOCKER run --name=${CONTAINER_NAME} \ 16 | --detach=true \ 17 | --restart=always \ 18 | --publish=123:123/udp \ 19 | --env=NTP_SERVERS=${NTP_SERVERS} \ 20 | --env=ENABLE_NTS=${ENABLE_NTS} \ 21 | --env=NOCLIENTLOG=${NOCLIENTLOG} \ 22 | --env=LOG_LEVEL=${LOG_LEVEL} \ 23 | --read-only=true \ 24 | --tmpfs=/etc/chrony:rw,mode=1750 \ 25 | --tmpfs=/run/chrony:rw,mode=1750 \ 26 | --tmpfs=/var/lib/chrony:rw,mode=1750 \ 27 | ${DOCKER_OPTS} \ 28 | ${IMAGE_NAME}:latest > /dev/null 29 | } 30 | 31 | # check if docker container with same name is already running. 32 | if [ "$(check_container)" != "" ]; then 33 | # container found... 34 | # 1) rename existing container 35 | $DOCKER rename ${CONTAINER_NAME} "${CONTAINER_NAME}_orig" > /dev/null 2>&1 36 | # 2) stop exiting container 37 | $DOCKER stop "${CONTAINER_NAME}_orig" > /dev/null 2>&1 38 | # 3) start new container 39 | start_container 40 | # 4) remover existing container 41 | if [ "$(check_container)" != "" ]; then 42 | $DOCKER rm "${CONTAINER_NAME}_orig" > /dev/null 2>&1 43 | fi 44 | 45 | # finally, lets clean up old docker images 46 | $DOCKER rmi $($DOCKER images -q ${IMAGE_NAME}) > /dev/null 2>&1 47 | 48 | # no docker container found. start a new one. 49 | else 50 | start_container 51 | fi 52 | -------------------------------------------------------------------------------- /vars: -------------------------------------------------------------------------------- 1 | # 2 | # this file contains a number of global variables used 3 | # by the docker container and its scripts. update any 4 | # of these to be appropriate for your environment. 5 | # 6 | 7 | IMAGE_NAME="cturra/ntp" 8 | CONTAINER_NAME="ntp" 9 | 10 | # (optional) define ntp server(s) to use 11 | # if none are provided a default is chosen 12 | # ntp server list must: be comma delimited and NOT contain spaces 13 | # NTP_SERVERS="time1.google.com,time2.google.com,time3.google.com,time4.google.com" 14 | NTP_SERVERS="time.cloudflare.com" 15 | 16 | # (optional) enable NTS in the chronyd configuration file 17 | ENABLE_NTS=false 18 | 19 | # (optional) turn on noclientlog option 20 | NOCLIENTLOG=false 21 | 22 | # (optional) define chrony log level to use 23 | # default: 0 24 | # options: 0 (informational), 1 (warning), 2 (non-fatal error), and 3 (fatal error) 25 | LOG_LEVEL=0 26 | 27 | # (optional) additional docker run options you may want 28 | DOCKER_OPTS="" 29 | --------------------------------------------------------------------------------