操作镜像
使用 docker 命令行操作 docker 镜像
获取镜像
使用「docker pull +镜像名称」从网络上下载image镜像
core@localhost ~ $ docker pull
Usage: docker pull NAME[:TAG]
Pull an image or a repository from the registry
core@localhost ~/php $ docker pull ubuntu
#pull +镜像的名称会下载该镜像集的laste tag的镜像
Pulling repository ubuntu
2185fd50e2ca: Pulling dependent layers
9cbaf023786c: Pulling dependent layers
3db9c44f4520: Pulling dependent layers
a9561eb1b190: Pulling dependent layers
195eb90b5349: Pulling dependent layers
463ff6be4238: Pulling dependent layers
c5881f11ded9: Pulling dependent layers
511136ea3c5a: Download complete
97fd97495e49: Downloading [=====> ] 6.868 MB/67.5 MB 10m20s
.....
core@localhost ~/php $ docker pull ubuntu:14.04
#表示下载该镜像集中14.04 tag的镜像
core@localhost ~/php $ docker pull dl.dockerpool.com:5000/alexeiled/docker-oracle-xe-11g
#下载其他非官方仓库中的镜像,一般网站会给出详细的 pull 命令
Pulling repository dl.dockerpool.com:5000/alexeiled/docker-oracle-xe-11g
ba16d5d5e1aa: Pulling image (latest) from dl.dockerpool.com:5000/alexeiled/docker-oracle-xe-11g, endpoint: http://dl.dockerpool.com:5000ba16d5d5e1aa: Download complete
8dbd9e392a96: Download complete
#这一串数字是表示文件系统的层次,docker 的镜像和容器就是这一层一层的文件系统组成的
215be6e94fbb: Download complete
ef2887b77b73: Download complete
97774de1565b: Download complete
c6a02636680f: Download complete
2ae911074081: Download complete
e1787c817b10: Download complete
5e312dc5fae8: Download complete
cb35ce95b58c: Download complete
5f0e28679c8e: Download complete
...
列出镜像
使用「docker images」列出本地宿主主机上拥有的image镜像
core@localhost ~ $ docker images
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
base/163 latest 468d347c06bc 28 hours ago 249.1 MB
test/supervisord latest 468d347c06bc 28 hours ago 249.1 MB
ubuntu 14.04 1357f421be38 4 days ago 192.7 MB
dl.dockerpool.com:5000/ubuntu 14.04 1357f421be38 4 days ago 192.7 MB
dl.dockerpool.com:5000/mysql 5.7 e95cbb9f48ea 6 days ago 258.6 MB
mysql 5.7 e95cbb9f48ea 6 days ago 258.6 MB
mysql latest 9a09222edf60 6 days ago 235.6 MB
tutum/lamp latest 4b32789c7d66 5 weeks ago 469.8 MB
tutum/tomcat 8.0 866eb07a675e 6 weeks ago 539.4 MB
tutum/tomcat latest 02e84f04100e 6 weeks ago 539.4 MB
dl.dockerpool.com:5000/alexeiled/docker-oracle-xe-11g latest ba16d5d5e1aa 7 months ago 2.388 GB
此处共有5列,分别表示镜像的名称、镜像的tag标记、镜像的唯一 image id、创建时间、大小
创建镜像
创建镜像的方法有 2 种:
1. 从文件系统导入
目前可用的文件系统主要是 openvz 的模板
比如:下载了一个ubuntu14.04的镜像 cat ubuntu-14.04-x86_64-minimal.tar.gz |docker import - ubuntu:14.04 然后用docker images看下:
core@localhost ~ $ docker images
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
ubuntu 14.04 05ac7c0b9383 17 seconds ago 215.5 MB
就多了一个我们的ubuntu镜像
2. 从 dockerfile 创建
dockerfile的内容后面章节详细介绍
3. 从现有的容器 commit 提交到一个新的 image
core@localhost ~ $ docker commit
Usage: docker commit [OPTIONS] CONTAINER [REPOSITORY[:TAG]]
Create a new image from a container's changes
-a, --author="" Author (e.g., "John Hannibal Smith <hannibal@a-team.com>")
#填写作者信息
-m, --message="" Commit message
#填写提交信息
-p, --pause=true Pause container during commit
#如果容器还在运行,先暂停容器
core@localhost ~ $ docker run -ti ubuntu:14.04 /bin/bash
#创建一个只有bash程序的容器
root@a925cb40b3f0:/# touch test
#在容器中建立一个文件
root@a925cb40b3f0:/# exit
#退出
exit
core@localhost ~ $ docker commit a92 for_test
#将刚才的容器提交为一个叫 for_test 的镜像,这里我们使用容器的 id 来指定我们要提交的容器,也可以使用容器的名字,他们都是唯一的
9e9c814023bcffc3e67e892a235afe61b02f66a947d2747f724bd317dda02f27
#返回新镜像的 id
core@localhost ~ $ docker images
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
for_test latest 9e9c814023bc 4 seconds ago 192.7 MB
删除镜像
使用「docker rmi + 镜像 id」删除镜像,当还有容器使用该镜像的时候是无法删除的。
core@localhost ~ $ docker rmi
Usage: docker rmi IMAGE [IMAGE...]
Remove one or more images
-f, --force=false Force removal of the image
--no-prune=false Do not delete untagged parents
core@localhost ~ $ docker images
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
for_test latest 60734a0ee3d6 3 seconds ago 192.7 MB
base/163 latest 468d347c06bc 29 hours ago 249.1 MB
test/supervisord latest 468d347c06bc 29 hours ago 249.1 MB
ubuntu 14.04 1357f421be38 4 days ago 192.7 MB
dl.dockerpool.com:5000/ubuntu 14.04 1357f421be38 4 days ago 192.7 MB
dl.dockerpool.com:5000/mysql 5.7 e95cbb9f48ea 6 days ago 258.6 MB
mysql 5.7 e95cbb9f48ea 6 days ago 258.6 MB
mysql latest 9a09222edf60 6 days ago 235.6 MB
tutum/lamp latest 4b32789c7d66 5 weeks ago 469.8 MB
tutum/tomcat 8.0 866eb07a675e 6 weeks ago 539.4 MB
tutum/tomcat latest 02e84f04100e 6 weeks ago 539.4 MB
dl.dockerpool.com:5000/alexeiled/docker-oracle-xe-11g latest ba16d5d5e1aa 7 months ago 2.388 GB
core@localhost ~ $ docker rmi 9a0
#当我们删除镜像 9a0 即 mysql:latest 镜像时,它删除了这个镜像所附带的所有aufs层
Untagged: mysql:latest
Deleted: 9a09222edf600a03ea48bd23cfa363841e45a8715237e3a58cb0167f0e8bad54
Deleted: 4daeda4ad839a152a3b649672bd5135977d7f81866d3bc0e16d0af3f65cc8af6
Deleted: cf07a411bf0883bd632940e8108dac49c64456a47f7390507de5685bbd6daf85
Deleted: 4f513746df18b222a07bb8d76d4b6d29752ce5dcb69bfad0ce92e6c1449a3821
Deleted: 228ecd435c8a29d25b77999036701a27f2d67874c915bb8eb9fb175b1f98aa60
Deleted: 37e4b3932afa186924a09eab332bc8ebec3aac8bac074314ed9a2d1e94547f50
Deleted: 898883ccfcee705e440547e30e240cb025c12410d7c9e4d2bcb11973ba075975
Deleted: 0a09ddcf99b7fd8fcb3525c41b54696038ecf13677f4459f1c98c742ffa60ab2
Deleted: 35bc8591e39be5089265a093e234d13a4b155a01d2ab9e8904eafa81664fb597
Deleted: 857e856e4481d59ee88a4cdedd9aaf855666bd494fa38506e6788361c0af4cda
core@localhost ~ $ docker ps
#使用 -ps 参数可以看到目前有上个容器在运行,其中一个容器是以tutum/lamp:laste镜像启动的