容器相关的命令

（对Docker感兴趣的朋友可以加我的微信ghostcloud2016，然后我把你加到我们的一个Docker爱好者群组里面。）

在上例中，我们用3种方式运行了容器，在上节中我们学习了：

• docker ps : 查看容器列表
• docker logs：查看容器的日志
• docker stop：停止容器 在本节中，我们将通过事例来熟悉一些其他的docker命令，并学习docker client。

1 Docker Client

Docker Client和Docker Daemon实际使用的是同一个二进制程序，通过docker --help命令可以直接查看docker的所有命令及选项：

查看docker可执行程序的路径：

root@shev:~# which docker /usr/bin/docker 

docker命令的帮助信息：

root@shev:~# docker --help Usage: docker [OPTIONS] COMMAND [arg...] docker daemon [ --help | ... ] docker [ --help | -v | --version ] A self-sufficient runtime for containers. Options: --config=~/.docker Location of client config files -D, --debug=false Enable debug mode --disable-legacy-registry=false Do not contact legacy registries -H, --host=[] Daemon socket(s) to connect to -h, --help=false Print usage -l, --log-level=info Set the logging level --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 -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 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 a container or image kill Kill a running container load Load an image from a tar archive or STDIN login Register or log in to a Docker registry logout Log out from a Docker registry logs Fetch the logs of a container network Manage Docker networks pause Pause all processes within a container 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 a 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(s) to a tar archive 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 a running container tag Tag an image into a repository top Display the running processes of a container unpause Unpause all processes within a container version Show the Docker version information volume Manage Docker volumes wait Block until a container stops, then print its exit code Run 'docker COMMAND --help' for more information on a command. 

具体的含义，我们在日后再一一讲解。我们先关注头几行：

Usage: docker [OPTIONS] COMMAND [arg...] docker daemon [ --help | ... ] docker [ --help | -v | --version ] 

剖析：

• 第一行实际是docker client的语法格式，它接收OPTIONS参数，并跟一个COMMAND，之后紧跟该命令对应的参数
• 第二行实际是docker daemon的语法格式，有兴趣的朋友可以通过docker daemon –help进行查看
• 第三行就是docker client的帮助，有需要都可以执行并查看。

一个我们经常用的查看docker版本信息的命令：

root@shev:~# docker version Client: Version: 1.9.0 API version: 1.21 Go version: go1.4.2 Git commit: 76d6bc9 Built: Tue Nov 3 17:43:42 UTC 2015 OS/Arch: linux/amd64 Server: Version: 1.9.0 API version: 1.21 Go version: go1.4.2 Git commit: 76d6bc9 Built: Tue Nov 3 17:43:42 UTC 2015 OS/Arch: linux/amd64 

这个命令会列出当前docker的client和server的基本信息.

2 通过容器来运行web应用

容器可以运行任何程序，那么一个主要的用途就是运行web应用，并对外提供服务，下面我们就用官方的一个例子来进行演示：

2.1 启动容器

root@shev:~# docker run -d -P training/webapp python app.py Unable to find image 'training/webapp:latest' locally latest: Pulling from training/webapp 2880a3395ede: Pull complete 515565c29c94: Pulling fs layer 98b15185dba7: Pulling fs layer 2ce633e3e9c9: Verifying Checksum 2ee0b8f351f7: Download complete 2505b734adda: Downloading [=====================> ] 8.732 MB/20.71 MB 20dd0c759013: Downloading [> ] 515.2 kB/50.25 MB f95ebd363bf2: Verifying Checksum 1952e3bf3d7e: Download complete abb991a4ed5e: Download complete 7cbae6914197: Pulling fs layer f74dd040041e: Pulling fs layer 54bb4e8718e8: Download complete Pulling repository docker.io/training/webapp 02a8815912ca: Download complete e9e06b06e14c: Download complete a82efea989f9: Download complete 37bea4ee0c81: Download complete 07f8e8c5e660: Download complete 23f0158a1fbe: Download complete 0a4852b23749: Download complete 7d0ff9745632: Download complete 99b0d955e85d: Download complete 33e109f2ff13: Download complete cc06fd877d54: Download complete b1ae241d644a: Download complete b37deb56df95: Download complete Status: Downloaded newer image for training/webapp:latest docker.io/training/webapp: this image was pulled from a legacy registry. Important: This registry version will not be supported in future versions of docker. 7736775bd89f6d0373b7a6c39a91126d156d9b0ce5467c30f0275506e012be4e 

我们查看一下程序是否启动：

root@shev:~# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 7736775bd89f training/webapp "python app.py" 9 minutes ago Up 9 minutes 0.0.0.0:32768->5000/tcp agitated_poitras e221abf45a0b ghostcloud.cn:5000/gcali:1.2 "/usr/local/ghostclou" About an hour ago Up About an hour gcsagent 

剖析：

• 我们从Docker Hub拉取了training用户下的webapp的最新版本，然后用python执行app.py
• 我们的启动参数包括:-d 在后台运行，-P导出容器需要导出的端口，由于Docker Hub在国外，因此拉取的时间可能会有点长，但是一旦本地有了镜像，之后就会很快了。
• 通过ps 命令，我们可以看到主机的32768端口映射到了容器的5000端口

2.2 访问网页

我们通过主机的32768端口进行访问： 

2.3 查看容器的端口导出情况

root@shev:~# docker port 7736 5000/tcp -> 0.0.0.0:32768 

2.4 查看容器的运行日志

root@shev:~# docker logs -f 7736 * Running on http://0.0.0.0:5000/ (Press CTRL+C to quit) 192.168.0.103 - - [02/Dec/2015 10:03:07] "GET / HTTP/1.1" 200 - 192.168.0.103 - - [02/Dec/2015 10:03:07] "GET /favicon.ico HTTP/1.1" 404 - 192.168.0.103 - - [02/Dec/2015 10:08:11] "GET / HTTP/1.1" 200 - 

剖析：

• -f会一直绑定到容器的标准输出上，不带-f时，运行后命令立刻就会退出
• 运行完logs –f后，我们访问网页时，就会在命令行里面显示日志

2.5 查看容器中的进程信息

root@shev:~# docker top 7736 UID PID PPID C STIME TTY TIME CMD root 5115 4051 0 17:53 ? 00:00:00 python app.py 

2.6 查看容器的详细信息

root@shev:~# docker inspect 7736 [ { "Id": "7736775bd89f6d0373b7a6c39a91126d156d9b0ce5467c30f0275506e012be4e", "Created": "2015-12-02T09:53:41.35592583Z", "Path": "python", "Args": [ "app.py" ], "State": { "Status": "running", "Running": true, "Paused": false, "Restarting": false, "OOMKilled": false, "Dead": false, "Pid": 5115, "ExitCode": 0, "Error": "", "StartedAt": "2015-12-02T09:53:41.62798274Z", "FinishedAt": "0001-01-01T00:00:00Z" }, "Image": "02a8815912ca800f99b7d912485e8c618260e27c6de8d7a161b356b322d5c121", "ResolvConfPath": "/var/lib/docker/containers/7736775bd89f6d0373b7a6c39a91126d156d9b0ce5467c30f0275506e012be4e/resolv.conf", "HostnamePath": "/var/lib/docker/containers/7736775bd89f6d0373b7a6c39a91126d156d9b0ce5467c30f0275506e012be4e/hostname", "HostsPath": "/var/lib/docker/containers/7736775bd89f6d0373b7a6c39a91126d156d9b0ce5467c30f0275506e012be4e/hosts", "LogPath": "/var/lib/docker/containers/7736775bd89f6d0373b7a6c39a91126d156d9b0ce5467c30f0275506e012be4e/7736775bd89f6d0373b7a6c39a91126d156d9b0ce5467c30f0275506e012be4e-json.log", "Name": "/agitated_poitras", "RestartCount": 0, "Driver": "aufs", "ExecDriver": "native-0.2", "MountLabel": "", "ProcessLabel": "", "AppArmorProfile": "", "ExecIDs": null, "HostConfig": { "Binds": null, "ContainerIDFile": "", "LxcConf": [], "Memory": 0, "MemoryReservation": 0, "MemorySwap": 0, "KernelMemory": 0, "CpuShares": 0, "CpuPeriod": 0, "CpusetCpus": "", "CpusetMems": "", "CpuQuota": 0, "BlkioWeight": 0, "OomKillDisable": false, "MemorySwappiness": -1, "Privileged": false, "PortBindings": {}, "Links": null, "PublishAllPorts": true, "Dns": null, "DnsOptions": null, "DnsSearch": null, "ExtraHosts": null, "VolumesFrom": null, "Devices": [], "NetworkMode": "default", "IpcMode": "", "PidMode": "", "UTSMode": "", "CapAdd": null, "CapDrop": null, "GroupAdd": null, "RestartPolicy": { "Name": "no", "MaximumRetryCount": 0 }, "SecurityOpt": null, "ReadonlyRootfs": false, "Ulimits": null, "LogConfig": { "Type": "json-file", "Config": {} }, "CgroupParent": "", "ConsoleSize": [ 0, 0 ], "VolumeDriver": "" }, "GraphDriver": { "Name": "aufs", "Data": null }, "Mounts": [], "Config": { "Hostname": "7736775bd89f", "Domainname": "", "User": "", "AttachStdin": false, "AttachStdout": false, "AttachStderr": false, "ExposedPorts": { "5000/tcp": {} }, "Tty": false, "OpenStdin": false, "StdinOnce": false, "Env": [ "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin" ], "Cmd": [ "python", "app.py" ], "Image": "training/webapp", "Volumes": null, "WorkingDir": "/opt/webapp", "Entrypoint": null, "OnBuild": null, "Labels": {}, "StopSignal": "SIGTERM" }, "NetworkSettings": { "Bridge": "", "SandboxID": "02c2de9e7171ed418869e53297b0b1956052be67d2c9c4c75f99829fff646fdd", "HairpinMode": false, "LinkLocalIPv6Address": "", "LinkLocalIPv6PrefixLen": 0, "Ports": { "5000/tcp": [ { "HostIp": "0.0.0.0", "HostPort": "32768" } ] }, "SandboxKey": "/var/run/docker/netns/02c2de9e7171", "SecondaryIPAddresses": null, "SecondaryIPv6Addresses": null, "EndpointID": "f623f99d87ec63cc3bfdc024886d24d40bd1cf1771e249951133a7c66424d6e9", "Gateway": "172.17.0.1", "GlobalIPv6Address": "", "GlobalIPv6PrefixLen": 0, "IPAddress": "172.17.0.2", "IPPrefixLen": 16, "IPv6Gateway": "", "MacAddress": "02:42:ac:11:00:02", "Networks": { "bridge": { "EndpointID": "f623f99d87ec63cc3bfdc024886d24d40bd1cf1771e249951133a7c66424d6e9", "Gateway": "172.17.0.1", "IPAddress": "172.17.0.2", "IPPrefixLen": 16, "IPv6Gateway": "", "GlobalIPv6Address": "", "GlobalIPv6PrefixLen": 0, "MacAddress": "02:42:ac:11:00:02" } } } } ] 

2.7 停止并重启容器

root@shev:~# docker stop 7736 7736 root@shev:~# root@shev:~# docker start 7736 7736 root@shev:~# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 7736775bd89f training/webapp "python app.py" 25 minutes ago Up 2 seconds 0.0.0.0:32769->5000/tcp agitated_poitras 

注意：容器的在主机上的映射端口变成了32769，原因是我们没有指定主机的端口。

2.8 指定主机和容器的端口映射

root@shev:~# docker run -d -p 80:5000 training/webapp python app.py 54132a474d29d44a7fc6431184ae1c1c77b4c8fb31975d477aab73647a008837 root@shev:~# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 54132a474d29 training/webapp "python app.py" 3 seconds ago Up 2 seconds 0.0.0.0:80->5000/tcp grave_williams 

剖析：

• 通过-p 参数可以指定端口映射，通过-P则是随机分配
• 由于我们导出主机的80端口，因此我们再次访问网页的时候，可以不需要指定端口： 

是不是眼前一亮，是的，我们可以将我们的网页直接运行在容器里面！ 想象一下，你拥有一台云主机……