Docker安装和基础用法 Docker入门教程第二篇

root@devstack:/home/sammy# docker --version
Docker version 1.12.1, build 23cf638

"State": {
      "Status": "running",
      "Running": true,
      "Paused": false,
      "Restarting": false,
      "OOMKilled": false,
      "Dead": false,
      "Pid": 4597,
      "ExitCode": 0,
      "Error": "",
      "StartedAt": "2016-09-16T08:09:34.53403504Z",
      "FinishedAt": "2016-09-16T08:06:44.365106765Z"
    }

root@devstack:/home/sammy# docker create --name web31 training/webapp python app.py #创建名字为 web31 的容器
7465f4cb7c49555af32929bd1bc4213f5e72643c0116450e495b71c7ec128502
root@devstack:/home/sammy# docker inspect --format='{{.State.Status}}' web31 #其状态为 created
created
root@devstack:/home/sammy# docker start web31 #启动容器
web31
root@devstack:/home/sammy# docker inspect --format='{{.State.Status}}' web31 #其状态为 running
running
root@devstack:/home/sammy# docker pause web31 #暂停容器
web31
root@devstack:/home/sammy# docker inspect --format='{{.State.Status}}' web31
paused
root@devstack:/home/sammy# docker unpause web31 #继续容器
web31
root@devstack:/home/sammy# docker inspect --format='{{.State.Status}}' web31
running
root@devstack:/home/sammy# docker rename web31 newweb31 #重命名
root@devstack:/home/sammy# docker inspect --format='{{.State.Status}}' newweb31
running
root@devstack:/home/sammy# docker top newweb31 #在容器中运行 top 命令
UID         PID         PPID        C          STIME        TTY         TIME        CMD
root        5009        4979        0          16:28        "htmlcode">

2016-09-16T16:01:18.206540853+08:00 container kill b3256ef1400a7f6a6f242e377a77af5e25d3b12237c4ee7c2e9b31a5f6437868 (image=training/webapp, name=web5, signal=15)
2016-09-16T16:01:38.212352224+08:00 container kill b3256ef1400a7f6a6f242e377a77af5e25d3b12237c4ee7c2e9b31a5f6437868 (image=training/webapp, name=web5, signal=9)
2016-09-16T16:01:38.235021315+08:00 container die b3256ef1400a7f6a6f242e377a77af5e25d3b12237c4ee7c2e9b31a5f6437868 (exitCode=137, image=training/webapp, name=web5)



能看到：
1.首先 docker 向容器发出 SIGTERM 信号（signal=15）

2.等待20秒 （01:18 到 01:38）

3.再发送 SIGKILL 系统信号 （signal = 9）

4.然后容器被杀掉了 （die）


而 docker kill 命令会直接发出SIGKILL的系统信号，以强行终止容器中程序的运行。运行 docker kill web5 命令后：
2016-09-16T16:06:44.351086471+08:00 container kill b3256ef1400a7f6a6f242e377a77af5e25d3b12237c4ee7c2e9b31a5f6437868 (image=training/webapp, name=web5, signal=9)

2016-09-16T16:06:44.365116100+08:00 container die b3256ef1400a7f6a6f242e377a77af5e25d3b12237c4ee7c2e9b31a5f6437868 (exitCode=137, image=training/webapp, name=web5)

可见直接发出的是 SIGKILL 信号，容器立马就被杀掉了。
（3）使用 docker cp 在 host 和 container 之间拷贝文件或者目录


root@devstack:/home/sammy# docker cp /home/sammy/mydockerbuild/Dockerfile web5:/webapp #从 host 拷贝文件到 container 里面
root@devstack:/home/sammy#
root@devstack:/home/sammy# docker cp web5:/webapp/Dockerfile /home/sammy/Dockerfile #从 container 里面拷贝文件到 host 上
root@devstack:/home/sammy# ls /home/sammy
chroot devstack Dockerfile mongodbdocker mydockerbuild webapp



（4）docker export 和 import
docker export：将一个容器的文件系统打包为一个压缩文件


root@devstack:/home/sammy# docker export web5 -o ./web5
root@devstack:/home/sammy# ls
chroot devstack Dockerfile mongodbdocker mydockerbuild web5 webapp



docker import：从一个压缩文件创建一个镜像


root@devstack:/home/sammy# docker import web5 web5img -m "imported on 0916"
sha256:745bb258be0a69a517367667646148bb2f662565bb3d222b50c0c22e5274a926
root@devstack:/home/sammy# docker history web5img
IMAGE        CREATED       CREATED BY     SIZE        COMMENT
745bb258be0a    6 seconds ago              324 MB       imported on 0916



 2.3 docker run 命令
docker run 命令会创建一个容器并启动它，它也是包含很多的参数，按照用途将它们分类如下：

   cgroups 和 namespace 相关：




   --blkio-weight value     Block IO (relative weight), between 10 and 1000
   --blkio-weight-device value  Block IO weight (relative device weight) (default [])
   --cgroup-parent string    Optional parent cgroup for the container
   --cpu-percent int       CPU percent (Windows only)
   --cpu-period int       Limit CPU CFS (Completely Fair Scheduler) period
   --cpu-quota int        Limit CPU CFS (Completely Fair Scheduler) quota
 -c, --cpu-shares int       CPU shares (relative weight)
   --cpuset-cpus string     CPUs in which to allow execution (0-3, 0,1)
   --cpuset-mems string     MEMs in which to allow execution (0-3, 0,1)
   --device-read-bps value    Limit read rate (bytes per second) from a device (default [])
   --device-read-iops value   Limit read rate (IO per second) from a device (default [])
   --device-write-bps value   Limit write rate (bytes per second) to a device (default [])
   --device-write-iops value   Limit write rate (IO per second) to a device (default [])
   --ipc string         IPC namespace to use
 -m, --memory string        Memory limit
   --memory-reservation string  Memory soft limit
   --memory-swap string     Swap limit equal to memory plus swap: '-1' to enable unlimited swap
   --memory-swappiness int    Tune container memory swappiness (0 to 100) (default -1)
   --kernel-memory string    Kernel memory limit
 -u, --user string         Username or UID (format: <name|uid>[:<group|gid>])
   --userns string        User namespace to use
   --uts string         UTS namespace to use
 -h, --hostname string       Container host name
   --pid string         PID namespace to use
   --pids-limit int       Tune container pids limit (set -1 for unlimited)
   --isolation string      Container isolation technology
   --io-maxbandwidth string   Maximum IO bandwidth limit for the system drive (Windows only)
   --io-maxiops uint       Maximum IOps limit for the system drive (Windows only)



linux process capabilities 相关参数：




   --cap-add value        Add Linux capabilities (default [])
   --cap-drop value       Drop Linux capabilities (default [])  




容器运行模式和环境相关：




 -d, --detach           Run container in background and print container ID
 -e, --env value          Set environment variables (default [])
 --env-file value       Read in a file of environment variables (default [])




DNS 相关：




   --dns value          Set custom DNS servers (default [])
   --dns-opt value        Set DNS options (default [])
   --dns-search value      Set custom DNS search domains (default [])





健康检查相关：




   --health-cmd string      Command to run to check health
   --health-interval duration  Time between running the check
   --health-retries int     Consecutive failures needed to report unhealthy
   --health-timeout duration   Maximum time to allow one check to run
   --no-healthcheck       Disable any container-specified HEALTHCHECK




IP 和端口：




   --ip string          Container IPv4 address (e.g. 172.30.100.104)
   --ip6 string         Container IPv6 address (e.g. 2001:db8::33)
 -p, --publish value        Publish a container's port(s) to the host (default [])
 -P, --publish-all         Publish all exposed ports to random ports
   --expose value        Expose a port or a range of ports (default [])
   --mac-address string     Container MAC address (e.g. 92:d0:c6:0a:29:33)
   --add-host value       Add a custom host-to-IP mapping (host:ip) (default [])



Volume 相关：




 -v, --volume value        Bind mount a volume (default [])
   --volume-driver string    Optional volume driver for the container
   --volumes-from value     Mount volumes from the specified container(s) (default [])
   --storage-opt value      Storage driver options for the container (default [])



Network 有关：




   --network string       Connect a container to a network (default "default")
   --network-alias value     Add network-scoped alias for the container (default [])
   --link value         Add link to another container (default [])
   --link-local-ip value     Container IPv4/IPv6 link-local addresses (default [])



日志有关：




   --log-driver string      Logging driver for the container
   --log-opt value        Log driver options (default [])





交互性有关：
 -a, --attach value        Attach to STDIN, STDOUT or STDERR (default [])
 -i, --interactive         Keep STDIN open even if not attached
  
  OOM 有关：  
   --oom-kill-disable      Disable OOM Killer
   --oom-score-adj int      Tune host's OOM preferences (-1000 to 1000)
  
  其它（待更进一步分类）：
   --cidfile string       Write the container ID to the file
   --detach-keys string     Override the key sequence for detaching a container
   --device value        Add a host device to the container (default [])
   --disable-content-trust    Skip image verification (default true)
   --entrypoint string      Overwrite the default ENTRYPOINT of the image
   --group-add value       Add additional groups to join (default [])
   --help            Print usage
 -l, --label value         Set meta data on a container (default [])
   --label-file value      Read in a line delimited file of labels (default [])
   --name string         Assign a name to the container
   --privileged         Give extended privileges to this container
   --read-only          Mount the container's root filesystem as read only
   --restart string       Restart policy to apply when a container exits (default "no")
   --rm             Automatically remove the container when it exits
   --runtime string       Runtime to use for this container
   --security-opt value     Security Options (default [])
   --shm-size string       Size of /dev/shm, default value is 64MB
   --sig-proxy          Proxy received signals to the process (default true)
   --stop-signal string     Signal to stop a container, SIGTERM by default (default "SIGTERM")
   --sysctl value        Sysctl options (default map[])
   --tmpfs value         Mount a tmpfs directory (default [])
 -t, --tty             Allocate a pseudo-TTY
   --ulimit value        Ulimit options (default [])
 -w, --workdir string       Working directory inside the container



具体的内容以后会有专门文件分析。
3. Doker 平台的基本构成

Docker 平台基本上由三部分组成：
客户端：用户使用 Docker 提供的工具（CLI 以及 API 等）来构建，上传镜像并发布命令来创建和启动容器

Docker 主机：从 Docker registry 上下载镜像并启动容器

Docker registry：Docker 镜像仓库，用于保存镜像，并提供镜像上传和下载

后面的文章会具体分析。
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。