如果你需要经常性需要多处部署同样的项目,如果你曾经也遇到过"明明在我电脑运行得好好的"问题,如果听说过 Docker 但还没用过,如果你不确定你到底需不需要 Docker ,那么,希望你花时间阅读一下这篇文章!
因为 Docker 将帮助你轻松运行自己不熟悉语言编写的开源项目,帮助你更加优雅地部署自己的项目,省去重复下载并配置环境的繁琐过程...
现在让我们先睹为快,预览一下基于 Docker 部署项目的实际效果,希望能让你对 Docker 有个初步的印象!
Docker部署的nginx作为反向代理服务器,支持https访问以及泛域名解析.
Docker部署的letsencrypt免费制作泛域名证书并整合反向代理服务nginx实现https访问.
Docker部署的nginx作为静态服务器,部署静态网站用于演示静态博客功能.
Docker部署的bark作为后端服务器,部署开源项目用于充当消息推送服务器.
Docker部署的webhook作为后端服务器,部署开源项目用于接收Webhook事件回调.
Docker部署的blog作为静态服务器,基于Github Action或Webhook实现博客内容自动更新并推送消息.
Github仓库内容更新后触发Github Action自动构建并部署远程服务器静态博客,同时发送的Webhook事件给webhook钩子容器,紧接着调用bark消息推送容器,实现消息推送到微信消息以及 app 通知.
Github仓库更新后自动运行Github Action源码构建静态博客并上传到远程服务器,blog容器会立即重启完成内容更新.
Github仓库更新后发送Webhooks到远程服务器,webhook容器接收到请求后转发给bark容器,进而推送给手机.
无论是熟悉的开源项目还是陌生的开源项目,Docker 让这些不一样变得一样,统一的管理方式使得使用成本大大降低,更加优雅地部署项目,真的不止是说说而已!
前提条件
目前在 Linux 系统上安装 Docker,对系统版本有以下要求:
- CentOS : 7
- Debian : 7.7(Wheezy LTS)、8.0(Jessie LTS)、9(Stretch)
- Fedora : 24、25
- Ubuntu : 16.04(Xenial LTS)、14.04(Trusty LTS)、17.04(Zesty)
一方面上述前提条件基本上新服务器都会满足,另一方面笔者对此并未深入实验,请读者自行验证,下面主要以 Centos7.6 为例讲解如何安装 Docker .
验证环境
对于新手来说,尽管安装 Docker 非常简单,但是总是不可避免地会遇到一些意外情况,或许是安装出错需要重新安装或者是不确定远程服务器是否已经安装,所以开始安装前还是先看一下到底有没有安装过 Docker 吧!
- 调用
docker命令
首先连接到远程服务器后运行 docker 命令,如果像下面那样输出一大堆用法介绍,那么证明 Docker 已经成功安装过,并且可能已经配置好相关环境了.
你现在唯一要做的就是学习一下 Docker 的基本用法,因为不用自己安装 Docker 环境,基本上也可以不必往下看了.
[root@snowdreams1006 ~]# docker Usage: docker [OPTIONS] COMMAND A self-sufficient runtime for containers Options: --config string Location of client config files (default "/root/.docker") -c, --context string Name of the context to use to connect to the daemon (overrides DOCKER_HOST env var and default context set with "docker context use") -D, --debug Enable debug mode -H, --host list Daemon socket(s) to connect to -l, --log-level string Set the logging level ("debug"|"info"|"warn"|"error"|"fatal") (default "info") --tls Use TLS; implied by --tlsverify --tlscacert string Trust certs signed only by this CA (default "/root/.docker/ca.pem") --tlscert string Path to TLS certificate file (default "/root/.docker/cert.pem") --tlskey string Path to TLS key file (default "/root/.docker/key.pem") --tlsverify Use TLS and verify the remote -v, --version Print version information and quit Management Commands: builder Manage builds config Manage Docker configs container Manage containers context Manage contexts engine Manage the docker engine image Manage images network Manage networks node Manage Swarm nodes plugin Manage plugins secret Manage Docker secrets service Manage services stack Manage Docker stacks swarm Manage Swarm system Manage Docker trust Manage trust on Docker images volume Manage volumes Commands: attach Attach local standard input, output, and error streams to a running container build Build an image from a Dockerfile commit Create a new image from a container's changes cp Copy files/folders between a container and the local filesystem create Create a new container diff Inspect changes to files or directories on a container's filesystem events Get real time events from the server exec Run a command in a running container export Export a container's filesystem as a tar archive history Show the history of an image images List images import Import the contents from a tarball to create a filesystem image info Display system-wide information inspect Return low-level information on Docker objects kill Kill one or more running containers load Load an image from a tar archive or STDIN login Log in to a Docker registry logout Log out from a Docker registry logs Fetch the logs of a container pause Pause all processes within one or more containers port List port mappings or a specific mapping for the container ps List containers pull Pull an image or a repository from a registry push Push an image or a repository to a registry rename Rename a container restart Restart one or more containers rm Remove one or more containers rmi Remove one or more images run Run a command in a new container save Save one or more images to a tar archive (streamed to STDOUT by default) search Search the Docker Hub for images start Start one or more stopped containers stats Display a live stream of container(s) resource usage statistics stop Stop one or more running containers tag Create a tag TARGET_IMAGE that refers to SOURCE_IMAGE top Display the running processes of a container unpause Unpause all processes within one or more containers update Update configuration of one or more containers version Show the Docker version information wait Block until one or more containers stop, then print their exit codes Run 'docker COMMAND --help' for more information on a command.
如果你输入 docker 提示 command not found ,说明服务器很可能并没有安装 Docker 环境,下面就教你如何一步一步安装 Docker 环境!
安装 Docker
Step 1: 移除旧版本
sudo yum remove docker \ docker-client \ docker-client-latest \ docker-common \ docker-latest \ docker-latest-logrotate \ docker-logrotate \ docker-engine
这一步是可选的,是因为最新版
Docker的名称已经发生了变化,为了保证安装的是最新版的Docker-CE,所以首先卸载可能已经安装过的旧版本.
Step 2: 安装必要系统依赖
sudo yum install -y yum-utils device-mapper-persistent-data lvm2
安装一些必要依赖,跟着官方教程说明走就好了,即使系统已存在该环境也可以再次运行,放心复制粘贴吧!
Step 3: 添加软件源信息
sudo yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
Step 4: 更新 yum 缓存
sudo yum makecache fast
Step 5: 安装 docker-ce
sudo yum -y install docker-ce
如果上述安装过程中没有出现任何报错,那么现在已经安装好基本的 Docker 环境!
启动 Docker
- 查看状态
sudo systemctl status docker
初次安装成功后默认是不会自动启动
Docker服务的,此时查看运行状态的输出结果不会包括Active: active (running)而是Active: inactive (dead).
- 首次启动
sudo systemctl start docker
安装后默认是没有启动
Docker服务的,因此安装后需要先启动Docker服务,再次查看运行状态sudo systemctl status docker应该会出现正在运行Active: active (running).
- 重新启动
sudo systemctl restart docker
如果
Docker服务已停止可以重新启动,如果已经启动也可以重新启动.
- 停止服务
sudo systemctl stop docker
如果正在运行的
Docker存在问题需要停止维修,那么可以先停止Docker服务,待维修结束后可以运行sudo systemctl start docker再次启动服务.
- 检查自启
systemctl list-unit-files | grep enabled | grep docker
检查
Docker服务是否会开机自启,如果存在结果则表示会开机自启,如果没有结果则表示不会开机自启.
- 开机自启
sudo systemctl enable docker
Docker服务是非常重要的进程服务,一般需要开机自启,保证意外关机后能自行恢复服务,推荐开机自启.
- 禁止自启
sudo systemctl disable docker
如果不小心设置了开机自启而你真的不打算开机自启的话,那么可以禁用开机自启功能,下次电脑重启后不会自动启动
Docker服务.
- 查看版本
docker version
查看当前安装的 Docker 版本信息,可以看出来主要分为两部分: Client: Docker Engine - Community 和 Server: Docker Engine - Community .
[root@snowdreams1006 ~]# docker version Client: Docker Engine - Community Version: 19.03.5 API version: 1.40 Go version: go1.12.12 Git commit: 633a0ea Built: Wed Nov 13 07:25:41 2019 OS/Arch: linux/amd64 Experimental: false Server: Docker Engine - Community Engine: Version: 19.03.5 API version: 1.40 (minimum version 1.12) Go version: go1.12.12 Git commit: 633a0ea Built: Wed Nov 13 07:24:18 2019 OS/Arch: linux/amd64 Experimental: false containerd: Version: 1.2.10 GitCommit: b34a5c8af56e510852c35414db4c1f4fa6172339 runc: Version: 1.0.0-rc8+dev GitCommit: 3e425f80a8c931f88e6d94a8c831b9d5aa481657 docker-init: Version: 0.18.0 GitCommit: fec3683
现在并不必关心具体的版本信息,只要运行 docker version 命令后能够输出类似信息即可,接下来开始真正的表演!
镜像加速
Docker 服务已经安装并启动,接下来我们可以基于 Docker 部署应用了,当然现在离真正部署自己的应用还有不小距离,但是我们可以运行公开的应用啊!
学习任何新语言的第一件事就是运行 hello world ,学习 Docker 容器化部署也不例外,我们也运行 Docker 版本的 hello world !
当我们敲入 docker run hello-world 命令后,终端会输出下列内容,只要输出 Hello from Docker! 字样就证明环境已经搭建完毕!
[root@snowdreams1006 ~]# docker run hello-world Unable to find image 'hello-world:latest' locally latest: Pulling from library/hello-world 1b930d010525: Pull complete Digest: sha256:4df8ca8a7e309c256d60d7971ea14c27672fc0d10c5f303856d7bc48f8cc17ff Status: Downloaded newer image for hello-world:latest Hello from Docker! This message shows that your installation appears to be working correctly. To generate this message, Docker took the following steps: 1. The Docker client contacted the Docker daemon. 2. The Docker daemon pulled the "hello-world" image from the Docker Hub. (amd64) 3. The Docker daemon created a new container from that image which runs the executable that produces the output you are currently reading. 4. The Docker daemon streamed that output to the Docker client, which sent it to your terminal. To try something more ambitious, you can run an Ubuntu container with: $ docker run -it ubuntu bash Share images, automate workflows, and more with a free Docker ID: https://hub.docker.com/ For more examples and ideas, visit: https://docs.docker.com/get-started/ [root@snowdreams1006 ~]#
如果你的网速比较慢,上述过程可能有一些耗时,但是如果你的网速一般而上述过程异常慢,很可能是因为你没有配置镜像!
因为 Docker 默认是先从国外下载项目到本地,然后再运行服务的,正如我们平时访问 Github 一样,那网速不是一般的慢!
Github 没有镜像加速地址并不能为我们加速访问,但是 Docker 项目仓库是有镜像仓库的,国内提供这种镜像服务的有不少,基本上都需要注册账号获取镜像地址之类的.
这里提供一下网易的镜像仓库地址 http://hub-mirror.c.163.com 以及阿里云的个人镜像仓库地址 https://8upnmlh3.mirror.aliyuncs.com .
只要将镜像地址配置给 Docker ,下一次再下载项目时速度应该就会得到明显提升!
首选打开并编辑 /etc/docker/daemon.json 文件,如果没有的话就新建该文件,内容如下:
{ "registry-mirrors": ["http://hub-mirror.c.163.com"] }
保存后重启 Docker 服务,试一试运行 docker pull nginx 会不会很快呢?
卸载 docker
假如发现意外想要重新安装 Docker 服务或者就是想要卸载 Docker ,那么只需要简单运行下列命令就能清除掉 Docker 环境!
sudo yum remove docker-ce sudo rm -rf /var/lib/docker
此时再次运行 docker 命令就会提示 command not found ,期待下一次相见会让人焕然一新!
基本命令
正如初次见面的那样,当我们成功安装 Docker 后控制台输出了一大堆关于用法的介绍,只不过当时年少轻狂并不在乎,蓦然回首,竟发现如此有用!
[root@snowdreams1006 ~]# docker Usage: docker [OPTIONS] COMMAND A self-sufficient runtime for containers Options: --config string Location of client config files (default "/root/.docker") -c, --context string Name of the context to use to connect to the daemon (overrides DOCKER_HOST env var and default context set with "docker context use") -D, --debug Enable debug mode -H, --host list Daemon socket(s) to connect to -l, --log-level string Set the logging level ("debug"|"info"|"warn"|"error"|"fatal") (default "info") --tls Use TLS; implied by --tlsverify --tlscacert string Trust certs signed only by this CA (default "/root/.docker/ca.pem") --tlscert string Path to TLS certificate file (default "/root/.docker/cert.pem") --tlskey string Path to TLS key file (default "/root/.docker/key.pem") --tlsverify Use TLS and verify the remote -v, --version Print version information and quit Management Commands: builder Manage builds config Manage Docker configs container Manage containers context Manage contexts engine Manage the docker engine image Manage images network Manage networks node Manage Swarm nodes plugin Manage plugins secret Manage Docker secrets service Manage services stack Manage Docker stacks swarm Manage Swarm system Manage Docker trust Manage trust on Docker images volume Manage volumes Commands: attach Attach local standard input, output, and error streams to a running container build Build an image from a Dockerfile commit Create a new image from a container's changes cp Copy files/folders between a container and the local filesystem create Create a new container diff Inspect changes to files or directories on a container's filesystem events Get real time events from the server exec Run a command in a running container export Export a container's filesystem as a tar archive history Show the history of an image images List images import Import the contents from a tarball to create a filesystem image info Display system-wide information inspect Return low-level information on Docker objects kill Kill one or more running containers load Load an image from a tar archive or STDIN login Log in to a Docker registry logout Log out from a Docker registry logs Fetch the logs of a container pause Pause all processes within one or more containers port List port mappings or a specific mapping for the container ps List containers pull Pull an image or a repository from a registry push Push an image or a repository to a registry rename Rename a container restart Restart one or more containers rm Remove one or more containers rmi Remove one or more images run Run a command in a new container save Save one or more images to a tar archive (streamed to STDOUT by default) search Search the Docker Hub for images start Start one or more stopped containers stats Display a live stream of container(s) resource usage statistics stop Stop one or more running containers tag Create a tag TARGET_IMAGE that refers to SOURCE_IMAGE top Display the running processes of a container unpause Unpause all processes within one or more containers update Update configuration of one or more containers version Show the Docker version information wait Block until one or more containers stop, then print their exit codes Run 'docker COMMAND --help' for more information on a command.
从零开始搭建服务器之更加优雅地部署项目（2）https://developer.aliyun.com/article/1542859
