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……
