一、获取镜像
命令格式：docker pull NAME:[TAG]
注：如果不显式地指定TAG，则默认会选择latest标签，即下载仓库中最新版本的镜像
例如：docker pull ubuntu
该命令实际上下载的就是从默认的注册服务器registry.hub.docker.com中ubuntu仓库下载最新的ubuntu:latest镜像。
用户也可以选择从其他的注册服务器仓库下载，例如从dockerpool社区镜像源dl.docker.com下载最新的Ubuntu镜像。
下载镜像到本地后，即可使用镜像了。例如利用 该镜像创建一个容器，在其中运行bash应用：docker run -t -i ubuntu / bin/bash
二、查看镜像信息
1.使用docker images命令可以列出本地主机上已有的镜像。
例如：docker images
REPOSITORY：来自哪个仓库
TAG：镜像的标签信息（区分标签的发行版本）
IMAGE ID：镜像ID号（唯一标识）
CREATED：创建时间
SIZE：镜像大小
2.使用docker inspect命令可以获取该镜像的详细信息。
例如：docker inspect ID
docker inspect 命令返回的是一个JSON格式的消息，如果只要其中一项内容，只需要使用-f参数来指定。
[
{
"Id": "sha256:0458a4468cbceea0c304de953305b059803f67693bad463dcbe7cce2c91ba670",
"RepoTags": [
"docker.io/ubuntu:latest"
],
"RepoDigests": [
"docker.io/ubuntu@sha256:e27e9d7f7f28d67aa9e2d7540bdc2b33254b452ee8e60f388875e5b7d9b2b696"
],
"Parent": "",
"Comment": "",
"Created": "2018-01-25T18:23:51.755470218Z",
"Container": "f28a4906bba09b098de298992e6cc2503f7376a47f2d8b5238a9bb49a41aa336",
"ContainerConfig": {
"Hostname": "f28a4906bba0",
"Domainname": "",
"User": "",
"AttachStdin": false,
"AttachStdout": false,
"AttachStderr": false,
"Tty": false,
"OpenStdin": false,
"StdinOnce": false,
"Env": [
"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
],
"Cmd": [
"/bin/sh",
"-c",
"#(nop) ",
"CMD [\"/bin/bash\"]"
],
"ArgsEscaped": true,
"Image": "sha256:c78f61863d4dc2b4f3e2e6999008fbb403d40328eda3370e00349bd0f9e88d40",
"Volumes": null,
"WorkingDir": "",
"Entrypoint": null,
"OnBuild": null,
"Labels": {}
},
"DockerVersion": "17.06.2-ce",
"Author": "",
"Config": {
"Hostname": "",
"Domainname": "",
"User": "",
"AttachStdin": false,
"AttachStdout": false,
"AttachStderr": false,
"Tty": false,
"OpenStdin": false,
"StdinOnce": false,
"Env": [
"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
],
"Cmd": [
"/bin/bash"
],
"ArgsEscaped": true,
"Image": "sha256:c78f61863d4dc2b4f3e2e6999008fbb403d40328eda3370e00349bd0f9e88d40",
"Volumes": null,
"WorkingDir": "",
"Entrypoint": null,
"OnBuild": null,
"Labels": null
},
"Architecture": "amd64",
"Os": "linux",
"Size": 111698050,
"VirtualSize": 111698050,
"GraphDriver": {
"Name": "devicemapper",
"Data": {
"DeviceId": "6",
"DeviceName": "docker-253:1-2031842-6f736c601216914269e22b598048e90091f78255fce8eeae8747a05ea3009f98",
"DeviceSize": "10737418240"
}
},
"RootFS": {
"Type": "layers",
"Layers": [
"sha256:ff986b10a018b48074e6d3a68b39aad8ccc002cdad912d4148c0f92b3729323e",
"sha256:9c7183e0ea88b265d83708dfe5b9189c4e12f9a1d8c3e5bce7f286417653f9b7",
"sha256:c98ef191df4b42c3fd5155d23385e75ee59707c6a448dfc6c8e4e9c005a3df11",
"sha256:92914665e7f61f8f19b56bf7983a2b3758cb617bef498b37adb80899e8b86e32",
"sha256:6f4ce6b888495c7c9bd4a0ac124b039d986a3b18250fa873d11d13b42f6a79f4"
]
}
}
]
