docker學習3：Docker容器使用

Docker 容器使用


Docker 客戶端
docker 客戶端非常簡單 ,我們可以直接輸入 docker 命令來檢視到 Docker 客戶端的所有命令選項。


[root@huixuan ~]# docker


Usage:  docker COMMAND


A self-sufficient runtime for containers


Options:
      --config string      Location of client config files (default "/root/.docker")
  -D, --debug              Enable debug mode
      --help               Print usage
  -H, --host list          Daemon socket(s) to connect to (default [])
  -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:
  container   Manage containers
  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
  volume      Manage volumes


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 between a container and the local filesystem
  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      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.
[root@huixuan ~]# 


可以透過命令 docker command --help 更深入的瞭解指定的 Docker 命令使用方法。
例如我們要檢視 docker stats 指令的具體使用方法：


[root@huixuan ~]# docker stats --help


Usage:  docker stats [OPTIONS] [CONTAINER...]


Display a live stream of container(s) resource usage statistics


Options:
  -a, --all             Show all containers (default shows just running)
      --format string   Pretty-print images using a Go template
      --help            Print usage
      --no-stream       Disable streaming stats and only pull the first result
[root@huixuan ~]# 


執行一個web應用
前面我們執行的容器並沒有一些什麼特別的用處。
接下來讓我們嘗試使用 docker 構建一個 web 應用程式。
我們將在docker容器中執行一個 Python Flask 應用來執行一個web應用。


[root@huixuan ~]# docker pull training/webapp  # 載入映象
Using default tag: latest
Trying to pull repository docker.io/training/webapp ... 
latest: Pulling from docker.io/training/webapp
e190868d63f8: Pull complete 
909cd34c6fd7: Pull complete 
0b9bfabab7c1: Pull complete 
a3ed95caeb02: Pull complete 
10bbbc0fc0ff: Pull complete 
fca59b508e9f: Pull complete 
e7ae2541b15b: Pull complete 
9dd97ef58ce9: Pull complete 
a4c1b0cb7af7: Pull complete 
Digest: sha256:06e9c1983bd6d5db5fba376ccd63bfa529e8d02f23d5079b8f74a616308fb11d
Status: Downloaded newer image for docker.io/training/webapp:latest
[root@huixuan ~]# docker run -d -P training/webapp python app.py
e4fbb06d2dda11414252575dd77b2561b23e09c0237fac764076ba61fffa3461
[root@huixuan ~]# 




引數說明:
-d:讓容器在後臺執行。
-P:將容器內部使用的網路埠對映到我們使用的主機上。




檢視 WEB 應用容器
使用 docker ps 來檢視我們正在執行的容器
[root@huixuan ~]# docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS                    NAMES
e4fbb06d2dda        training/webapp     "python app.py"     37 seconds ago      Up 35 seconds       0.0.0.0:1024->5000/tcp   kickass_wright
[root@huixuan ~]# 


這裡多了埠資訊。
PORTS  
0.0.0.0:1024->5000/tcp 


Docker 開放了 5000 埠（預設 Python Flask 埠）對映到主機埠 32769 上。
這時我們可以透過瀏覽器訪問WEB應用