3.4 基本指令及用法

Docker 的基本指令及用法详解

Docker官方为了让用户快速了解Docker，提供了一个交互式教程，旨在帮助用户掌握Docker命令行的使用方法。但是由于Docker技术的快速发展，此交互式教程已经无法满足Docker用户的实际使用需求，所以让我们一起开始一次真正的命令行学习之旅。首先，Docker的命令清单可以通过运行 docker ，或者 docker help 命令得到:

$ sudo docker --help
Usage: docker [OPTIONS] COMMAND [arg...]

A self-sufficient runtime for linux containers.

Options:
--add-registry=[]                    Registry to query before a public one
  --api-cors-header=                   Set CORS headers in the remote API
  -b, --bridge=                        Attach containers to a network bridge
  --bip=                               Specify network bridge IP
  --block-registry=[]                  Don't contact given registry
  --confirm-def-push=true              Confirm a push to default registry
  -D, --debug=false                    Enable debug mode
  -d, --daemon=false                   Enable daemon mode
  --default-gateway=                   Container default gateway IPv4 address
  --default-gateway-v6=                Container default gateway IPv6 address
  --default-ulimit=[]                  Set default ulimits for containers
  --dns=[]                             DNS server to use
  --dns-search=[]                      DNS search domains to use
  -e, --exec-driver=native             Exec driver to use
  --exec-opt=[]                        Set exec driver options
  --exec-root=/var/run/docker          Root of the Docker execdriver
  --fixed-cidr=                        IPv4 subnet for fixed IPs
  --fixed-cidr-v6=                     IPv6 subnet for fixed IPs
  -G, --group=docker                   Group for the unix socket
  -g, --graph=/var/lib/docker          Root of the Docker runtime
  -H, --host=[]                        Daemon socket(s) to connect to
  -h, --help=false                     Print usage
  --icc=true                           Enable inter-container communication
  --insecure-registry=[]               Enable insecure registry communication
  --ip=0.0.0.0                         Default IP when binding container ports
  --ip-forward=true                    Enable net.ipv4.ip_forward
  --ip-masq=true                       Enable IP masquerading
  --iptables=true                      Enable addition of iptables rules
  --ipv6=false                         Enable IPv6 networking
  -l, --log-level=info                 Set the logging level
  --label=[]                           Set key=value labels to the daemon
  --log-driver=json-file               Default driver for container logs
  --log-opt=map[]                      Set log driver options
  --mtu=0                              Set the containers network MTU
  -p, --pidfile=/var/run/docker.pid    Path to use for daemon PID file
  --registry-mirror=[]                 Preferred Docker registry mirror
  -s, --storage-driver=                Storage driver to use
  --selinux-enabled=false              Enable selinux support
  --storage-opt=[]                     Set storage driver options
  --tls=false                          Use TLS; implied by --tlsverify
  --tlscacert=~/.docker/ca.pem         Trust certs signed only by this CA
  --tlscert=~/.docker/cert.pem         Path to TLS certificate file
  --tlskey=~/.docker/key.pem           Path to TLS key file
  --tlsverify=false                    Use TLS and verify the remote
  --userland-proxy=true                Use userland proxy for loopback traffic
  -v, --version=false                  Print version information and quit

Commands:
    attach    Attach 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 from a container's filesystem to the host path
    create    Create a new container
    diff      Inspect changes on a container's filesystem
    events    Get real time events from the server
    exec      Run a command in a running container
    export    Stream the contents of a container as a tar archive
    history   Show the history of an image
    images    List images
    import    Create a new filesystem image from the contents of a tarball
    info      Display system-wide information
    inspect   Return low-level information on a container or image
    kill      Kill a running container
    load      Load an image from a tar archive
    login     Register or log in to a Docker registry server
    logout    Log out from a Docker registry server
    logs      Fetch the logs of a container
    pause     Pause all processes within a container
    port      Lookup the public-facing port that is NAT-ed to PRIVATE_PORT
    ps        List containers
    pull      Pull an image or a repository from a Docker registry server
    push      Push an image or a repository to a Docker registry server
    rename    Rename an existing container
    restart   Restart a running container
    rm        Remove one or more containers
    rmi       Remove one or more images
    run       Run a command in a new container
    save      Save an image to a tar archive
    search    Search for an image on the Docker Hub
    start     Start a stopped container
    stats     Display a stream of a containers' resource usage statistics
    stop      Stop a running container
    tag       Tag an image into a repository
    top       Lookup the running processes of a container
    unpause   Unpause a paused container
    version   Show the Docker version information
    wait      Block until a container stops, then print its exit code

Run 'docker COMMAND --help' for more information on a command.

在Docker容器技术不断演化的过程中，Docker的子命令已经达到39个之多，其中核心子命令(例如：run)还会有复杂的参数配置。笔者通过结合功能和应用场景方面的考虑，把命令行划分为4个部分，方便我们快速概览Docker命令行的组成结构：

1.参数约定

单个字符的参数可以放在一起组合配置，例如

$ sudo docker run -t -i --name test centos sh

可以用这样的方式等同：

$ sudo docker run -ti --name test centos sh

2.Boolean

Boolean参数形式如： -d=false。注意，当你声明这个Boolean参数时，比如 docker run -d=true，它将直接把启动的Container挂起放在后台运行。

3.字符串和数字

参数如 --name=“” 定义一个字符串，它仅能被定义一次。同类型的如-c=0 定义一个数字，它也只能被定义一次。

4.后台进程

Docker后台进程是一个常驻后台的系统进程，值得注意的是Docker使用同一个文件来支持客户端和后台进程，其中角色切换通过-d来实现。这个后台进程是用来管理容器的:

注意，其中带有[] 的启动参数可以指定多次，例如:

$ sudo docker run -a stdin -a stdout -a stderr -i -t ubuntu /bin/bash