如何编写Prometheus的Dockerfile并构建启动容器镜像？

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目录+从官方镜像启动：prom/prometheus+官方Dockerfile分析+编写自己的Dockerfile+构建镜像：+启动容器：+从官方镜像启动：prom/prometheus+拉取镜像：$ docker pull prom/prometheus+启动容器方式1：$ doc

目录

• 从官方镜像启动：prom/prometheus
• 官方Dockerfile分析
• 编写自己的Dockerfile
  • 构建镜像：
  • 启动容器：

从官方镜像启动：prom/prometheus

拉取镜像

$ docker pull prom/prometheus

启动容器

方式1：

$ docker run -td -p 9090:9090 --name prometheus1 prom/prometheus

方式2：路径挂载

$ docker run \ -p 9090:9090 \ -v /path/to/prometheus.yml:/etc/prometheus/prometheus.yml \ prom/prometheus $ docker run \ -p 9090:9090 \ -v /path/to/config:/etc/prometheus \ prom/prometheus 官方Dockerfile分析

官方Dockerfile文件如下

ARG ARCH="amd64" ARG OS="linux" FROM quay.io/prometheus/busybox-${OS}-${ARCH}:latest LABEL maintainer="The Prometheus Authors <prometheus-developers@googlegroups.com>" ARG ARCH="amd64" ARG OS="linux" COPY .build/${OS}-${ARCH}/prometheus /bin/prometheus COPY .build/${OS}-${ARCH}/promtool /bin/promtool COPY documentation/examples/prometheus.yml /etc/prometheus/prometheus.yml COPY console_libraries/ /usr/share/prometheus/console_libraries/ COPY consoles/ /usr/share/prometheus/consoles/ COPY LICENSE /LICENSE COPY NOTICE /NOTICE COPY npm_licenses.tar.bz2 /npm_licenses.tar.bz2 WORKDIR /prometheus RUN ln -s /usr/share/prometheus/console_libraries /usr/share/prometheus/consoles/ /etc/prometheus/ && \ chown -R nobody:nobody /etc/prometheus /prometheus USER nobody EXPOSE 9090 VOLUME [ "/prometheus" ] ENTRYPOINT [ "/bin/prometheus" ] CMD [ "--config.file=/etc/prometheus/prometheus.yml", \ "--storage.tsdb.path=/prometheus", \ "--web.console.libraries=/usr/share/prometheus/console_libraries", \ "--web.console.templates=/usr/share/prometheus/consoles" ]

从官网Dockerfile文件可知：

1. 使用busybox作为基础镜像
2. 拷贝相关文件（prometheus、promtool、prometheus.yml等）到指定目录（/bin、/etc）
3. 指定工作目录/prometheus
4. 容器内端口9090
5. 指定默认匿名卷为"/prometheus"，Prometheus运行产生的数据将写到宿主机相关目录
6. ENTRYPOINT容器启动入口点为"/bin/prometheus"
7. CMD指定容器启动参数为："--config.file=/etc/prometheus/prometheus.yml", "--storage.tsdb.path=/prometheus","--web.console.libraries=/usr/share/prometheus/console_libraries", "--web.console.templates=/usr/share/prometheus/consoles"

容器内Prometheus启动命令为：

/bin/prometheus --config.file=/etc/prometheus/prometheus.yml --storage.tsdb.path=/prometheus --web.console.libraries=/usr/share/prometheus/console_libraries --web.console.templates=/usr/share/prometheus/consoles

进入容器查看Prometheus的进程：

[root@docker ~]# docker exec -it prometheus1 sh /prometheus $ /prometheus $ ps -ef | grep prometheu[s] 1 nobody 0:53 /bin/prometheus --config.file=/etc/prometheus/prometheus.yml --storage.tsdb.path=/prometheus --web.console.libraries=/usr/share/prometheus/console_libraries --web.console.templates=/usr/share/prometheus/consoles 编写自己的Dockerfile

这里编写自己的Dockerfile进行构建，开启Prometheus进程的配置热加载和数据库管理功能。

FROM amd64/busybox:1.35 LABEL maintainer="The Prometheus Authors <wuenwuen>" ARG ARCH="amd64" ARG OS="linux" COPY prometheus-*.${OS}-${ARCH}/prometheus /prometheus/bin/ COPY prometheus-*.${OS}-${ARCH}/promtool /prometheus/bin/ COPY prometheus-*.${OS}-${ARCH}/prometheus.yml /prometheus/etc/prometheus.yml COPY prometheus-*.${OS}-${ARCH}/console_libraries/* /prometheus/console_libraries/ COPY prometheus-*.${OS}-${ARCH}/consoles/* /prometheus/consoles/ COPY prometheus-*.${OS}-${ARCH}/LICENSE /prometheus/LICENSE COPY prometheus-*.${OS}-${ARCH}/NOTICE /prometheus/NOTICE WORKDIR /prometheus RUN ln -s /prometheus/bin/prometheus /prometheus/bin/promtool /bin/ && \ chown -R root:root /prometheus USER root EXPOSE 9090 VOLUME [ "/prometheus/data", "/prometheus/etc" ] ENTRYPOINT [ "/bin/prometheus" ] CMD [ "--config.file=/prometheus/etc/prometheus.yml", \ "--storage.tsdb.path=/prometheus/data", \ "--web.console.libraries=/prometheus/console_libraries", \ "--web.console.templates=/prometheus/consoles", \ "--web.enable-lifecycle", \ "--web.enable-admin-api" ]

解读：

1. 使用amd64/busybox:1.35作为基础镜像，将Prometheus的二进制文件放入bin目录，将配置文件统一放入etc目录；
2. 将配置文件目录和数据存储目录定义为匿名卷；
3. 启动方式中，新增两项配置，开启配置文件的热加载和数据库管理功能。

在同目录下添加一个.dockerignore文件，来屏蔽一些无关构建的文件：

prometheus-*.linux-amd64.tar.gz etc 构建镜像：

新建目录，将版本包和Dockerfile文件放入该目录

# mkdir /root/prometheus;cd /root/prometheus # ls Dockerfile prometheus-2.33.1.linux-amd64.tar.gz

解压版本包，同时新建.dockerignore文件，在该文件下添加与构建无关的文件或目录（这表示构建时，不将这些文件复制到构建上下文环境中）

# tar -zxf prometheus-2.33.1.linux-amd64.tar.gz # cat .dockerignore prometheus-*.linux-amd64.tar.gz

执行构建命令docker build

$ docker build -t prometheus:v1 . Sending build context to Docker daemon 200.8MB Step 1/18 : FROM amd64/busybox:1.35 ---> 96b2896db672 Step 2/18 : LABEL maintainer="The Prometheus Authors <wuenwuen>" ---> Running in 04e215d3c3e0 Removing intermediate container 04e215d3c3e0 ---> 88050ed9e09d Step 3/18 : ARG ARCH="amd64" ---> Running in 5ce5d1b12e0f Removing intermediate container 5ce5d1b12e0f ---> 370832a62c71 Step 4/18 : ARG OS="linux" ---> Running in d7ea847b2d90 Removing intermediate container d7ea847b2d90 ---> cf9781cb7722 Step 5/18 : COPY prometheus-*.${OS}-${ARCH}/prometheus /prometheus/bin/ ---> 42b4b03f8332 Step 6/18 : COPY prometheus-*.${OS}-${ARCH}/promtool /prometheus/bin/ ---> 897066bd0ca3 Step 7/18 : COPY prometheus-*.${OS}-${ARCH}/prometheus.yml /prometheus/etc/prometheus.yml ---> b141fa2c22a6 Step 8/18 : COPY prometheus-*.${OS}-${ARCH}/console_libraries/* /prometheus/console_libraries/ ---> 228b62d5e860 Step 9/18 : COPY prometheus-*.${OS}-${ARCH}/consoles/* /prometheus/consoles/ ---> 5c9125f39322 Step 10/18 : COPY prometheus-*.${OS}-${ARCH}/LICENSE /prometheus/LICENSE ---> c89f57bbceb6 Step 11/18 : COPY prometheus-*.${OS}-${ARCH}/NOTICE /prometheus/NOTICE ---> 7e459dfd86fe Step 12/18 : WORKDIR /prometheus ---> Running in 8f09cea3e03e Removing intermediate container 8f09cea3e03e ---> ee1f386d159b Step 13/18 : RUN ln -s /prometheus/bin/prometheus /prometheus/bin/promtool /bin/ && chown -R root:root /prometheus ---> Running in 093e9b6b8d14 Removing intermediate container 093e9b6b8d14 ---> 121df7a93221 Step 14/18 : USER root ---> Running in b4ffed0d491a Removing intermediate container b4ffed0d491a ---> 75e2aada4653 Step 15/18 : EXPOSE 9090 ---> Running in b09e22947d56 Removing intermediate container b09e22947d56 ---> c700606bd44d Step 16/18 : VOLUME [ "/prometheus/data", "/prometheus/etc" ] ---> Running in e18dd4f3af2a Removing intermediate container e18dd4f3af2a ---> 824d398febdd Step 17/18 : ENTRYPOINT [ "/bin/prometheus" ] ---> Running in ff8fb122f2fb Removing intermediate container ff8fb122f2fb ---> 414d2523bb9b Step 18/18 : CMD [ "--config.file=/prometheus/etc/prometheus.yml", "--storage.tsdb.path=/prometheus/data", "--web.console.libraries=/prometheus/console_libraries", "--web.console.templates=/prometheus/consoles", "--web.enable-lifecycle", "--web.enable-admin-api" ] ---> Running in 56a8542d31a9 Removing intermediate container 56a8542d31a9 ---> 17f5fa014281 Successfully built 17f5fa014281 Successfully tagged prometheus:v1

查看构建的镜像：

$ docker images REPOSITORY TAG IMAGE ID CREATED SIZE prometheus v1 17f5fa014281 6 minutes ago 403MB amd64/busybox 1.35 96b2896db672 2 weeks ago 1.24MB prom/prometheus latest a3d385fc29f9 2 months ago 201MB # 可以看到自己构建的镜像比官方镜像大了一倍 启动容器：

直接启动：

$ docker run -td prometheus:v1 $ docker run -td -p 9090:9090 prometheus:v1

直接启动后，配置文件和数据存储目录将默认使用匿名挂载。

挂载路径使用docker inspect命令查看

路径挂载（推荐）：

选择挂载出配置文件目录，数据存储目录使用默认的匿名挂载就行了。

由于路径挂载时，容器内挂载路径下的文件会被隐藏，同时Prometheus的启动又需要指定配置文件，所以启动容器前，需要提前将配置文件放在挂载点路径下，以避免容器启动后Prometheus进程无法启动，导致容器退出。

新建挂载点，并存放配置文件：

$ tree /root/prometheus/etc /root/prometheus/etc ├── first_rules.yml ├── prometheus.yml └── static_config └── node_exporter.yml

然后就可以使用构建的镜像来启动容器了，命令如下

# 选择其中一个即可 $ docker -td -v /root/prometheus/etc:/prometheus/etc prometheus:v1 $ docker run -td -p 9090:9090 --name prometheus-1 -v /root/prometheus/etc:/prometheus/etc prometheus:v1 $ docker run \ -td -p 9090:9090 --name prometheus-1 \ -v /root/prometheus/etc:/prometheus/etc \ prometheus:v1

查看容器：

$ docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES b2ebd62251ac prometheus:v1 "/bin/prometheus --c…" About a minute ago Up About a minute 0.0.0.0:9090->9090/tcp, :::9090->9090/tcp prometheus-1 $ docker ps --format "table {{.Image}}\t{{.ID}}\t{{.Ports}}\t{{.Status}}\t{{.Names}}" IMAGE CONTAINER ID PORTS STATUS NAMES prometheus:v1 b2ebd62251ac 0.0.0.0:9090->9090/tcp, :::9090->9090/tcp Up 6 minutes prometheus-1

访问Prometheus的UI界面：192.168.175.130:9090/

天行健，君子以自强不息；地势坤，君子以厚德载物。