查看镜像信息

查看镜像的命令通常有：images、history和inspect，info等子命令

images

列出系统已下载好的所有镜像基础信息

**REPOSITORY**:表示来自于哪个仓库。
**TAG**:表示镜像的标签信息，标签只是标记，并不能标识镜像内容。
**IMAGE ID**:镜像ID，镜像的唯一标识，如果两个镜像ID相同，则说明它们实际上指向了同一个镜像，只是具有不同标签名而已。
**CREATED**:表示镜像最后的更新时间。
**VIRTUAL SIZE**:表示镜像大小，好的镜像往往体积会较小。

其他可选命令:

  -a, --all             Show all images (default hides intermediate images)
      --digests         Show digests
  -f, --filter filter   Filter output based on conditions provided
      --format string   Pretty-print images using a Go template
      --no-trunc        Don't truncate output
  -q, --quiet           Only show image IDs

inspect

获取镜像的详细信息，包括制作者、适应架构、各层的数字摘要等内容

语法如下：

docker inspect [imageName]

docker inspect gitlab/gitlab-runner

输出结果

[
  {
    "Id": "sha256:4a05b6a7fca0ccf20f17f27e8de0050265efc9f1ccb046c22b5fda79f196e5d3",
    "RepoTags": [
      "gitlab/gitlab-runner:latest"
    ],
    "RepoDigests": [
      "gitlab/gitlab-runner@sha256:885f5c60a3788453add33a57e1b1690dca4f1e27e84fa1c26976f13bb6949599"
    ],
    "Parent": "",
    "Comment": "buildkit.dockerfile.v0",
    "Created": "2021-11-21T17:44:24.533835743Z",
    "Container": "",
    "ContainerConfig": {
      "Hostname": "",
      "Domainname": "",
      "User": "",
      "AttachStdin": false,
      "AttachStdout": false,
      "AttachStderr": false,
      "Tty": false,
      "OpenStdin": false,
      "StdinOnce": false,
      "Env": null,
      "Cmd": null,
      "Image": "",
      "Volumes": null,
      "WorkingDir": "",
      "Entrypoint": null,
      "OnBuild": null,
      "Labels": null
    },
    "DockerVersion": "",
    "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",
        "DEBIAN_FRONTEND=noninteractive"
      ],
      "Cmd": [
        "run",
        "--user=gitlab-runner",
        "--working-directory=/home/gitlab-runner"
      ],
      "ArgsEscaped": true,
      "Image": "",
      "Volumes": {
        "/etc/gitlab-runner": {},
        "/home/gitlab-runner": {}
      },
      "WorkingDir": "",
      "Entrypoint": [
        "/usr/bin/dumb-init",
        "/entrypoint"
      ],
      "OnBuild": null,
      "Labels": null,
      "StopSignal": "SIGQUIT"
    },
    "Architecture": "amd64",
    "Os": "linux",
    "Size": 2014374536,
    "VirtualSize": 2014374536,
    "GraphDriver": {
      "Data": {
        "LowerDir": "/var/lib/docker/overlay2/e045b0d7cede39f731b84d105f588d1600fe8ac4da42a42f3964d9484ed81a6f/diff:/var/lib/docker/overlay2/5ab1dcf2c94b178717d9148884438d8a7cfb79d47f995c898a4af043ad4cb44d/diff:/var/lib/docker/overlay2/bcb1539f1156a1866c1f667c592d74991bfe844ee5e94458ef7462153f7cbc9c/diff:/var/lib/docker/overlay2/543257feb8c81525eafb3d3fea19fad76b5acd51635c88871cc724a9bf356ebd/diff:/var/lib/docker/overlay2/13718e59b573721c362fc8f9ed7fe4ee55490b0883c764fe25193f753a00756c/diff",
        "MergedDir": "/var/lib/docker/overlay2/e7816f7523b9d4d5ad834ff25be1fa12d1a2e7488a271dfc7322ee1bd3e4c192/merged",
        "UpperDir": "/var/lib/docker/overlay2/e7816f7523b9d4d5ad834ff25be1fa12d1a2e7488a271dfc7322ee1bd3e4c192/diff",
        "WorkDir": "/var/lib/docker/overlay2/e7816f7523b9d4d5ad834ff25be1fa12d1a2e7488a271dfc7322ee1bd3e4c192/work"
      },
      "Name": "overlay2"
    },
    "RootFS": {
      "Type": "layers",
      "Layers": [
        "sha256:9f54eef412758095c8079ac465d494a2872e02e90bf1fb5f12a1641c0d1bb78b",
        "sha256:cb42c96bf5a2978289ed421a6fa0ada6d7d134d75f1fccaceb79199f728a5e1c",
        "sha256:46529c561e988adf92a39892f06fece04866a029a73cfcc7fd0142c82901c77d",
        "sha256:80b981c4da2e54fc0fd00df83d9f3b2a48902e6175cfccecafc43392dd6873db",
        "sha256:7e7650a4f42fdbd05e8d99a3c24ec8c5f7ab6eb9f3b8ae28ad63e24c81313618",
        "sha256:439f627256739a2bf2a47b1facedfbbd0b30df71e3493b2a8b5c16af50bc6ba7"
      ]
    },
    "Metadata": {
      "LastTagTime": "0001-01-01T00:00:00Z"
    }
  }
]

上面返回的是一个JSON格式的消息，如果只要其中某一项的内容时，可以使用-f来指定，语法格式

docker insepect -f {{".项名(keyName)"}} 镜像名

如我想查容器Id

[root@Vue ~]# docker inspect -f {{".Id"}} gitlab/gitlab-runner
>>> sha256:4a05b6a7fca0ccf20f17f27e8de0050265efc9f1ccb046c22b5fda79f196e5d3

更为详细的 inspect命令其它操作
https://blog.csdn.net/yuelai_217/article/details/125266030

history

查看镜像历史
Docker的镜像文件是由多个层组成，那么我们怎么才知道各层的内容具体是什么呢?
因此可以使用history命令，该命令将列出各层的创建信息。
命令：

docker history [imageName]

示例：

docker history gitlab/gitlab-runner

这个时候发现 CREATED BY 中显示的命令过长的话会被隐藏此时我们可以使用—no-trunc 选项来输出完整命令。
语法：

docker history gitlab/gitlab-runner --no-trunc

其他可选参数：

      --format string   Pretty-print images using a Go template
  -H, --human           Print sizes and dates in human readable format (default true)
      --no-trunc        Don't truncate output
  -q, --quiet           Only show image IDs

查看Docker版本

docker -v
docker --version
docker version

查看Docker运行相关信息

docker info