Docker入门笔记

Docker

获取镜像

docker image pull

$ docker pull ubuntu:18.04

查看镜像

docker image ls

$ docker image ls
REPOSITORY                         TAG                 IMAGE ID            CREATED             SIZE
openzipkin/zipkin                  latest              9b4acc3eb019        2 months ago        150MB
ubuntu                             18.04               2c047404e52d        3 months ago        63.3MB

# 或者
$ docker images

# 过滤出ubuntu的镜像
$ docker images ubuntu

给镜像打标签 docker tag

# 打标签
$ docker tag ubuntu:18.04 myubuntu:18.04

# 再查出来
# 注意：myubuntu 和 ubuntu 镜像id是一样的！！！myubuntu镜像只是在2c047404e52d镜像上打个标签而已
$ docker images *ubuntu
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
myubuntu            18.04               2c047404e52d        3 months ago        63.3MB
ubuntu              18.04               2c047404e52d        3 months ago        63.3MB

查看详细信息 docker inspect

$ docker image inspect ubuntu:18.04
[
    {
        "Id": "sha256:2c047404e52d7f17bdac4121a13cd844447b74e13063f8cb8f8b314467feed06",
        "RepoTags": [
            "myubuntu:18.04",
            "ubuntu:18.04"
        ],
        "RepoDigests": [
            "ubuntu@sha256:fd25e706f3dea2a5ff705dbc3353cf37f08307798f3e360a13e9385840f73fb3"
        ],
        "Parent": "",
        "Comment": "",
        "Created": "2020-11-25T22:25:17.102901455Z",
        "Container": "360f37005f8aa084aa4a0de8a51b991a359599a40637783b3ceb0ffbe3a78d71",
        // ........
    }
]

查看镜像历史 docker history

$ docker history ubuntu:18.04
IMAGE               CREATED             CREATED BY                                      SIZE                COMMENT
2c047404e52d        3 months ago        /bin/sh -c #(nop)  CMD ["/bin/bash"]            0B                  
<missing>           3 months ago        /bin/sh -c mkdir -p /run/systemd && echo 'do…   7B                  
<missing>           3 months ago        /bin/sh -c [ -z "$(apt-get indextargets)" ]     0B                  
<missing>           3 months ago        /bin/sh -c set -xe   && echo '#!/bin/sh' > /…   745B                
<missing>           3 months ago        /bin/sh -c #(nop) ADD file:6ef542de9959c3061…   63.3MB           

搜寻镜像

docker search

$ docker search --filter=is-official=true nginx

$ docker search --filter=stars=4 tensorflow

删除镜像

根据标签删除镜像 docker image rm

# 删除 myubuntu, 
# ubuntu 标签的镜像还引用相同镜像id的镜像
# 所以只会移除 myubuntu 标签
$ docker image rm myubuntu:18.04
Untagged: myubuntu:18.04

# 删除 ubuntu
# 此时已经没有其他标签引用了
# 所以会彻底删除
$ docker image rm ubuntu:18.04
Untagged: ubuntu:18.04
Untagged: ubuntu@sha256:fd25e706f3dea2a5ff705dbc3353cf37f08307798f3e360a13e9385840f73fb3
Deleted: sha256:2c047404e52d7f17bdac4121a13cd844447b74e13063f8cb8f8b314467feed06
Deleted: sha256:9459b6a89846db0723e467610b841e6833dbb2aae6133319a91f2f70c388afac
Deleted: sha256:9a9311f7fcddf94f7476ce89f9703e8360e8cf347ef486a280735f5cf98888cd
Deleted: sha256:b43408d5f11b7b2faf048ae4eb25c296536c571fb2f937b4f1c3883386e93d64

根据镜像id删除镜像 docker image rm

# 查看一下，目前 myubuntu 和 ubuntu 都是相同的镜像id
$ docker image ls *ubuntu
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
ubuntu              18.04               2c047404e52d        3 months ago        63.3MB
myubuntu            18.04               2c047404e52d        3 months ago        63.3MB

# 尝试用镜像id删除
$ docker image rm 2c047404e52d
Error response from daemon: conflict: unable to delete 2c047404e52d (must be forced) - image is referenced in multiple repositories

# 先根据镜像标签删一个
$ docker image rm myubuntu:18.04
Untagged: myubuntu:18.04

# 再用镜像id删，这次就成功了
$ docker image rm 2c047404e52d
Untagged: ubuntu:18.04
Untagged: ubuntu@sha256:fd25e706f3dea2a5ff705dbc3353cf37f08307798f3e360a13e9385840f73fb3
Deleted: sha256:2c047404e52d7f17bdac4121a13cd844447b74e13063f8cb8f8b314467feed06
Deleted: sha256:9459b6a89846db0723e467610b841e6833dbb2aae6133319a91f2f70c388afac
Deleted: sha256:9a9311f7fcddf94f7476ce89f9703e8360e8cf347ef486a280735f5cf98888cd
Deleted: sha256:b43408d5f11b7b2faf048ae4eb25c296536c571fb2f937b4f1c3883386e93d64

删除虚悬镜像 docker image prune

$ dokcer image prune

创建镜像

docker commit

# 基于ubuntu镜像启动一个容器，并进入到容器的bash
$ docker run -it ubuntu:18.04 /bin/bash

# 在容器中创建一个测试文件，然后退出容器，记住容器的 id 5f470c986c61
root@5f470c986c61:/# touch test.txt
root@5f470c986c61:/# exit
exit

# 通过提交容器创建镜像
$ docker container commit -m "add test file" -a "some info" 5f470c986c61
sha256:ed81f7211c7f6e22a02f2f7a8425537bfef3359db2fad870cdc62240fe146f69

docker import

注：了解即可

# 基于本地模板导入
# 到 https://wiki.openvz.org/Download/template/precreated 下载OpenVZ提供的模板
# 下面 “import - ubuntu:18:04” 中的-是表示从标准输入流读取文件信息
$ cat ubuntu-18.04-x86-minimal.tar.gz | docker container import - ubuntu:18:04

docker build

新建一个mypython3目录，进入目录然后创建一个Dockerfile

$ mkdir mypython3
$ cd mypython3
$ vim Dockerfile

然后写一个简单的Dockerfile文件：

FROM debian:stretch-slim
LABEL version="1.0" maintainer="caibh"
RUN apt-get update && 
	apt-get install -y python3 && 
	apt-get clean && 
	rm -rf /var/lib/apt/lists/*

然后构建镜像：

caibh@book:~/mypython3$ docker build -t mypython3:1.0 .

导入导出

docker save

# 导出镜像到本地文件系统
$ docker save -o ubuntu_18.04.tar ubuntu:18.04
$ ll
总用量 64120
-rw------- 1 caibh caibh 65652224 2月  25 17:59 ubuntu_18.04.tar

docker load

# 删除镜像
$ docker image rm ubuntu:18.04

# 从本地导入镜像
$ docker load -i ubuntu_18.04.tar 
b43408d5f11b: Loading layer [==================================================>]  65.62MB/65.62MB
23135df75b44: Loading layer [==================================================>]  15.87kB/15.87kB
fe6d8881187d: Loading layer [==================================================>]  3.072kB/3.072kB
Loaded image: ubuntu:18.04

# 查看导出的镜像
$ docker image ls ubuntu
REPOSITORY                         TAG                 IMAGE ID            CREATED             SIZE
ubuntu                             18.04               2c047404e52d        3 months ago        63.3MB

上传镜像

docker push