Docker 笔记（二）–镜像

记录Docker 安装操作记录，便于查询。

参考

1. 链接: Docker 入门到实战教程(三)镜像和容器
2. 链接: docker中daemon.json各配置详解
3. 链接: docker容器/etc/docker/daemon.json配置文件详解
4. 链接: docker官方文档

环境

Centos 7.9

操作

1.查看命令

// 查看全部命令
[root@centos7-18 image]# docker command --help 

// 查看某一个命令，例如查看run
[root@centos7-18 image]# docker run --help 

2.查询镜像

// 查询nginx命令
[root@centos7-18 image]# docker search nginx
NAME                               DESCRIPTION                                      STARS     OFFICIAL   AUTOMATED
nginx                              Official build of Nginx.                         19234     [OK]       
unit                               Official build of NGINX Unit: Universal Web …   17        [OK]       
nginxinc/nginx-unprivileged        Unprivileged NGINX Dockerfiles                   133
nginx/nginx-ingress                NGINX and  NGINX Plus Ingress Controllers fo…   86                   
nginx/nginx-prometheus-exporter    NGINX Prometheus Exporter for NGINX and NGIN…   33                                                      

• Name：源名称
• DESCRIPTION：描述
• STARS：星（点赞）数量
• OFFICIAL：是否官方发布
• AUTOMATED：是否自动构建

3.拉取镜像

// 默认拉取最新版
[root@centos7-18 image]# docker pull nginx
Using default tag: latest
latest: Pulling from library/nginx
a2abf6c4d29d: Pull complete 
a9edb18cadd1: Pull complete 
589b7251471a: Pull complete 
186b1aaa4aa6: Pull complete 
b4df32aa5a72: Pull complete 
a0bcbecc962e: Pull complete 
Digest: sha256:0d17b565c37bcbd895e9d92315a05c1c3c9a29f762b011a10c54a66cd53c9b31
Status: Downloaded newer image for nginx:latest
docker.io/library/nginx:latest                                                     

4.查看镜像

4.1. 查看所有镜像

[root@centos7-18 image]# docker images
REPOSITORY   TAG       IMAGE ID       CREATED         SIZE
nginx        latest    605c77e624dd   22 months ago   141MB
redis        latest    7614ae9453d1   23 months ago   113MB                                                 

• REPOSITORY：表示镜像的仓库源
• TAG：标签
• IMAGE ID：ID
• CREATED：创建时间
• SIZE：大小
  4.2. 查看镜像详细信息

[root@centos7-18 image]# docker inspect nginx
[{"Id": "sha256:605c77e624ddb75e6110f997c58876baa13f8754486b461117934b24a9dc3a85","RepoTags": ["nginx:latest"],"RepoDigests": ["nginx@sha256:0d17b565c37bcbd895e9d92315a05c1c3c9a29f762b011a10c54a66cd53c9b31"],"Parent": "","Comment": "","Created": "2021-12-29T19:28:29.892199479Z","Container": "ca3e48389f7160bc9d9a892d316fcbba459344ee3679998739b1c3cd8e56f7da","ContainerConfig": {"Hostname": "ca3e48389f71","Domainname": "","User": "","AttachStdin": false,"AttachStdout": false,"AttachStderr": false,"ExposedPorts": {"80/tcp": {}},"Tty": false,"OpenStdin": false,"StdinOnce": false,"Env": ["PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin","NGINX_VERSION=1.21.5","NJS_VERSION=0.7.1","PKG_RELEASE=1~bullseye"],"Cmd": ["/bin/sh","-c","#(nop) ","CMD [\"nginx\" \"-g\" \"daemon off;\"]"],"Image": "sha256:82941edee2f4d17c55563bb926387c3ae39fa1a99777f088bc9d3db885192209","Volumes": null,"WorkingDir": "","Entrypoint": ["/docker-entrypoint.sh"],"OnBuild": null,"Labels": {"maintainer": "NGINX Docker Maintainers <docker-maint@nginx.com>"},"StopSignal": "SIGQUIT"},"DockerVersion": "20.10.7","Author": "","Config": {"Hostname": "","Domainname": "","User": "","AttachStdin": false,"AttachStdout": false,"AttachStderr": false,"ExposedPorts": {"80/tcp": {}},"Tty": false,"OpenStdin": false,"StdinOnce": false,"Env": ["PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin","NGINX_VERSION=1.21.5","NJS_VERSION=0.7.1","PKG_RELEASE=1~bullseye"],"Cmd": ["nginx","-g","daemon off;"],"Image": "sha256:82941edee2f4d17c55563bb926387c3ae39fa1a99777f088bc9d3db885192209","Volumes": null,"WorkingDir": "","Entrypoint": ["/docker-entrypoint.sh"],"OnBuild": null,"Labels": {"maintainer": "NGINX Docker Maintainers <docker-maint@nginx.com>"},"StopSignal": "SIGQUIT"},"Architecture": "amd64","Os": "linux","Size": 141479488,"VirtualSize": 141479488,"GraphDriver": {"Data": {"LowerDir": "/var/lib/docker/overlay2/8b0be5030647522bf7b1b39db844d8c650bd8133a00ac05b330879de438c0abb/diff:/var/lib/docker/overlay2/563d515cbd4227114e7adeb014737ce26c3238a9e54135141519c5870470a0e0/diff:/var/lib/docker/overlay2/690c4f6a17cb8cf1aabe042511f57c198281895336138ac474117c60a879cc30/diff:/var/lib/docker/overlay2/3de8af079b18dd20b726da9ce7a91836810e1effd694cc39cccfc63925626d2c/diff:/var/lib/docker/overlay2/b04d78c79c57a4b680bf3f66c56a33b683fd632182f630835ec67d3a400ff965/diff","MergedDir": "/var/lib/docker/overlay2/fd8c77083cd9b2c0c9bd36ecf8ade515986d4d9cf536abea70ecb0440fed2907/merged","UpperDir": "/var/lib/docker/overlay2/fd8c77083cd9b2c0c9bd36ecf8ade515986d4d9cf536abea70ecb0440fed2907/diff","WorkDir": "/var/lib/docker/overlay2/fd8c77083cd9b2c0c9bd36ecf8ade515986d4d9cf536abea70ecb0440fed2907/work"},"Name": "overlay2"},"RootFS": {"Type": "layers","Layers": ["sha256:2edcec3590a4ec7f40cf0743c15d78fb39d8326bc029073b41ef9727da6c851f","sha256:e379e8aedd4d72bb4c529a4ca07a4e4d230b5a1d3f7a61bc80179e8f02421ad8","sha256:b8d6e692a25e11b0d32c5c3dd544b71b1085ddc1fddad08e68cbd7fda7f70221","sha256:f1db227348d0a5e0b99b15a096d930d1a69db7474a1847acbc31f05e4ef8df8c","sha256:32ce5f6a5106cc637d09a98289782edf47c32cb082dc475dd47cbf19a4f866da","sha256:d874fd2bc83bb3322b566df739681fbd2248c58d3369cb25908d68e7ed6040a6"]},"Metadata": {"LastTagTime": "0001-01-01T00:00:00Z"}}
]                                               

4.3. 查看镜像中间层

[root@centos7-18 image]# docker images -a                                              

如果不同镜像之间有复用的中间层，这里就会看见一些没有镜像名和标签的镜像，很多镜像依赖这些中间层，所以中间层镜像是不能随意删除的。
4.4. 查看镜像中间层

[root@centos7-18 image]# docker images -a                                              

5.删除镜像

5.1. 删除镜像

// 删除镜像
[root@centos7-18 image]# docker rmi hello-world
// 强制删除镜像  
[root@centos7-18 image]# docker rmi -f hello-world                                         

5.2. 删除虚悬镜像

[root@centos7-18 image]# docker image prune                                      

docker images (不加-a)显示的没有名称和标签的镜像叫虚悬镜像，没有实际用途，可以清除。

6.导出镜像

[root@centos7-18 ~]# docker save -o hello-word.tar hello-world
[root@centos7-18 ~]# ls
anaconda-ks.cfg  hello-word.tar

• -o 参数后面接着输出文件名。
• hello-world是需要导出的镜像名。

7.导入镜像

[root@centos7-18 ~]# docker load -i hello-word.tar 
e07ee1baac5f: Loading layer [==================================================>]  14.85kB/14.85kB
Loaded image: hello-world:latest

8.修改镜像名和TAG

[root@centos7-18 ~]# docker tag hello-world:latest hello-world:1.0
[root@centos7-18 ~]# docker tag hello-world:latest hello-demo:1.0
[root@centos7-18 ~]# docker images
REPOSITORY    TAG       IMAGE ID       CREATED         SIZE
nginx         latest    605c77e624dd   22 months ago   141MB
redis         latest    7614ae9453d1   23 months ago   113MB
hello-demo    1.0       feb5d9fea6a5   2 years ago     13.3kB
hello-world   1.0       feb5d9fea6a5   2 years ago     13.3kB
hello-world   latest    feb5d9fea6a5   2 years ago     13.3kB

9.镜像存储位置

9.1. 存储位置

• linux保存在“/var/lib/docker/”；
• windows保存在“C:\ProgramData\DockerDesktop”
• Mac保存在“com.docker.docker/Data/vms/0/”

9.2. 修改位置
修改镜像存储与运行加载目录

[root@centos7-18 ~]# vim /etc/docker/daemon.json{"data-root": "/data/var/lib/docker",
}

[root@centos7-18 docker]# systemctl daemon-reload 
[root@centos7-18 docker]# systemctl restart docker