一、Docker镜像相关操作¶
1.1 官方仓库拉取镜像¶
1、执行docker image pull ubuntu:latest命令下载镜像。
root@zq-virtual-machine:/home/zq/Desktop# docker image pull ubuntu:latest
2、执行docker image ls命令查看刚才下载的镜像。
root@zq-virtual-machine:/home/zq/Desktop# docker image ls
REPOSITORY TAG IMAGE ID CREATED SIZE
ubuntu latest 2dc39ba059dc 4 weeks ago 77.8MB
1.2 非官方仓库拉取镜像¶
1、执行docker image pull nigelpoultion/tu-demo:v2命令下载镜像,此命令意思是从Docker Hub账户为nigelpoultion中名为tu-demo库中下载标签为v2的镜像。
root@zq-virtual-machine:/home/zq/Desktop# docker image pull nigelpoultion/tu-demo:v2
2、执行docker image ls命令查看刚才下载的镜像。
1.3 第三方仓库(非docker仓库)拉取镜像¶
1、执行docker pull gcr.io/nigelpoultion/tu-demo:v2命令下载镜像,此命令意思是从谷歌容器镜像仓库服务中且Docker Hub账户为nigelpoultion中名为tu-demo库中下载标签为v2的镜像。
root@zq-virtual-machine:/home/zq/Desktop# docker pull gcr.io/nigelpoultion/tu-demo:v2
2、执行docker image ls命令查看刚才下载的镜像。
1.4 为镜像打多个标签¶
1、执行docker image pull -a nigelpoultion/tu-demo命令拉取仓库中的全部镜像。
root@zq-virtual-machine:/home/zq/Desktop# docker image pull -a nigelpoultion/tu-demo
2、执行docker image ls命令查看刚才下载的镜像。
1.5 过滤docker image ls输出内容¶
1、执行docker image ls --filter dangling=true命令返回悬虚(dangling)镜像，一般在列表展示为<none>:<none>。
root@zq-virtual-machine:/var/lib/docker# docker image ls --filter dangling=true
REPOSITORY TAG IMAGE ID CREATED SIZE
2、执行docker image ls --filter dangling=false命令返回非悬虚(dangling)镜像。
root@zq-virtual-machine:/var/lib/docker# docker image ls --filter dangling=false
REPOSITORY TAG IMAGE ID CREATED SIZE
ubuntu latest 2dc39ba059dc 4 weeks ago 77.8MB
3、执行docker image ls --filter=reference="*:latest"命令完成过滤并且仅显示标签为latest。
root@zq-virtual-machine:/var/lib/docker# docker image ls --filter=reference="*:latest"
REPOSITORY TAG IMAGE ID CREATED SIZE
ubuntu latest 2dc39ba059dc 4 weeks ago 77.8MB
4、执行docker image ls --format "{{.Size}}"命令只返回Docker主机上镜像的大小属性。
root@zq-virtual-machine:/var/lib/docker# docker image ls --format "{{.Size}}"
77.8MB
5、执行docker image ls --format "{{.Size}} : {{.Tag}} : {{.Size}}"命令返回全部镜像，但是只显示仓库、标签和大小信息。
root@zq-virtual-machine:/var/lib/docker# docker image ls --format "{{.Size}} : {{.Tag}} : {{.Size}}"
77.8MB : latest : 77.8MB
1.6 CLI方式搜索Docker Hub¶
1、执行docker search nigelpoulton命令查找所有"NAME"包含"nigelpoulton"的仓库。
root@zq-virtual-machine:/var/lib/docker# docker search nigelpoulton
NAME DESCRIPTION STARS OFFICIAL AUTOMATED
nigelpoulton/pluralsight-docker-ci Simple web app used in my Pluralsight video … 27 [OK]
nigelpoulton/tu-demo Voting web server used for various Pluralsig… 16
nigelpoulton/getting-started-k8s Node.js web app 9
nigelpoulton/gsd Getting Started with Docker -- Pluralsight v… 6
nigelpoulton/k8sbook Simple web app used for demos in The Kuberne… 4
nigelpoulton/ctr-demo Web server for simple Docker demos 3
nigelpoulton/nginxadapter Slightly modified NGINX image for use in Plu… 1
nigelpoulton/ps-web Simple web app used in Pluralsight courses. 1
nigelpoulton/vote Fork of dockersamples Voting App for *Docker… 1
nigelpoulton/hello-cloud Quick hello-world container image used for D… 0
nigelpoulton/msb-hello 0
nigelpoulton/web-app Web app for use in Pluralsight multi-contain… 0
nigelpoulton/acg-web Simple web app for A Cloud Guru Kubernetes D… 0
nigelpoulton/msb-web 0
nigelpoulton/web-fe1 Web front end 0
nigelpoulton/workshop101 Kubernetes 101 Workshop. 0
nigelpoulton/lke-nodebalancer Node.js webserver for Linode LKE demos 0
nigelpoulton/curl Simple *curl* container for use in demos and… 0
nigelpoulton/k8s-deep-dive Images for use in Kubernetes Deep Dive book 0
nigelpoulton/dockerbook Repo for examples used in Docker Deep Dive b… 0
nigelpoulton/ddd-web Web server for use in Docker Deep Dive partn… 0
nigelpoulton/qsk-book Images for use in *Quick Start Kubernetes* b… 0
nigelpoulton/web Demo Node.js web app used in Docker Deep Div… 0
nigelpoulton/k8s101-sksh Images for Kubernetes 101 course on Skillsha… 0
nigelpoulton/k8s-api-proxy 0
说明:关于docker search，默认情况下，只返回25行结果；可以指定--limit参数来增加返回内容行数，最多为100行!!! 2、执行docker search alpine命令列出所有仓库名称中包含"alpine"的镜像。
root@zq-virtual-machine:/var/lib/docker# docker search alpine
NAME DESCRIPTION STARS OFFICIAL AUTOMATED
alpine A minimal Docker image based on Alpine Linux… 9256 [OK]
alpinelinux/docker-cli Simple and lightweight Alpine Linux image wi… 5
alpinelinux/gitlab-runner Alpine Linux gitlab-runner (supports more ar… 3
alpinelinux/alpine-gitlab-ci Build Alpine Linux packages with Gitlab CI 3
alpinelinux/gitlab-runner-helper Helper image container gitlab-runner-helper … 1
grafana/alpine Alpine Linux with ca-certificates package in… 1
alpinelinux/package-builder Container to build packages for a repository 1
rancher/alpine-git 1
alpinelinux/golang Build container for golang based on Alpine L… 1
alpinelinux/build-base Base image suitable for building packages wi… 0
alpinelinux/docker-abuild Dockerised abuild 0
alpinelinux/darkhttpd 0
alpinelinux/docker-compose docker-compose image based on Alpine Linux 0
alpinelinux/unbound 0
alpinelinux/docker-alpine 0
alpinelinux/mqtt-exec 0
alpinelinux/apkbuild-lint-tools Tools for linting APKBUILD files in a CI env… 0
alpinelinux/mirror-status 0
alpinelinux/git-mirror-syncd 0
alpinelinux/alpine-docker-gitlab Gitlab running on Alpine Linux 0
alpinelinux/rsyncd 0
alpinelinux/alpine-drone-ci Build Alpine Linux packages with drone CI 0
alpinelinux/ansible Ansible in docker 0
alpinelinux/secdb 0
alpinelinux/aports-qa-bot A Gitlab bot that gives feedback on aports m… 0
说明:关于docker search，默认情况下，只返回25行结果；可以指定--limit参数来增加返回内容行数，最多为100行!!! 3、执行docker search alpine --filter "is-official=true"命令列出官方alpine的镜像。
root@zq-virtual-machine:/var/lib/docker# docker search alpine --filter "is-official=true"
NAME DESCRIPTION STARS OFFICIAL AUTOMATED
alpine A minimal Docker image based on Alpine Linux… 9256 [OK]
说明:关于docker search，默认情况下，只返回25行结果；可以指定--limit参数来增加返回内容行数，最多为100行!!! 4、执行docker search alpine --filter "is-automated=true"命令只显示自动创建的仓库。
root@zq-virtual-machine:/var/lib/docker# docker search alpine --filter "is-automated=true"
NAME DESCRIPTION STARS OFFICIAL AUTOMATED
说明:关于docker search，默认情况下，只返回25行结果；可以指定--limit参数来增加返回内容行数，最多为100行!!!
1.7 查看镜像分层¶
1、执行docker image inspect ubuntu:latest命令查看镜像分层方式。这里观察到"Layers"后面只有一个SHA256散列值来标识镜像层。代表该镜像只包含一个镜像层。
root@zq-virtual-machine:/var/lib/docker# docker image inspect ubuntu:latest
[
{
"Id": "sha256:2dc39ba059dcd42ade30aae30147b5692777ba9ff0779a62ad93a74de02e3e1f",
"RepoTags": [
"ubuntu:latest"
],
"RepoDigests": [
"ubuntu@sha256:20fa2d7bb4de7723f542be5923b06c4d704370f0390e4ae9e1c833c8785644c1"
],
"Parent": "",
"Comment": "",
"Created": "2022-09-01T23:46:35.375057619Z",
"Container": "b0df58d0a952d2cb3b35163ac557fe1886c0fe5cf73a82a16491a22089aadb8c",
"ContainerConfig": {
"Hostname": "b0df58d0a952",
"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 [\"bash\"]"
],
"Image": "sha256:1f88c721b49061df8bcee6398193b3642df4f089f9343e138302473c3d58fc06",
"Volumes": null,
"WorkingDir": "",
"Entrypoint": null,
"OnBuild": null,
"Labels": {}
},
"DockerVersion": "20.10.12",
"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": [
"bash"
],
"Image": "sha256:1f88c721b49061df8bcee6398193b3642df4f089f9343e138302473c3d58fc06",
"Volumes": null,
"WorkingDir": "",
"Entrypoint": null,
"OnBuild": null,
"Labels": null
},
"Architecture": "amd64",
"Os": "linux",
"Size": 77830458,
"VirtualSize": 77830458,
"GraphDriver": {
"Data": {
"DeviceId": "2",
"DeviceName": "docker-8:5-1065834-64b7546962b390b4619e08ed872bf043fa8afe203860c2298207a62080170efa",
"DeviceSize": "10737418240"
},
"Name": "devicemapper"
},
"RootFS": {
"Type": "layers",
"Layers": [
"sha256:7f5cbd8cc787c8d628630756bcc7240e6c96b876c2882e6fc980a8b60cdfa274"
]
},
"Metadata": {
"LastTagTime": "0001-01-01T00:00:00Z"
}
}
]
1.8 根据摘要拉取镜像¶
下面先在Docker主机上删除ubuntu:latest镜像，然后根据摘要再次拉取ubuntu:latest镜像。 1、执行docker image ls --digests ubuntu命令查看在本地查看镜像摘要-基于其内容的密码散列值。这里观察到DIGEST值为sha256:20fa2d7bb4de7723f542be5923b06c4d704370f0390e4ae9e1c833c8785644c1。
root@zq-virtual-machine:/var/lib/docker# docker image ls --digests ubuntu
REPOSITORY TAG DIGEST IMAGE ID CREATED SIZE
ubuntu latest sha256:20fa2d7bb4de7723f542be5923b06c4d704370f0390e4ae9e1c833c8785644c1 2dc39ba059dc 4 weeks ago 77.8MB
2、执行docker image rm ubuntu:latest命令删除ubuntu:latest镜像。
root@zq-virtual-machine:/var/lib/docker# docker image rm ubuntu:latest
Untagged: ubuntu:latest
Untagged: ubuntu@sha256:20fa2d7bb4de7723f542be5923b06c4d704370f0390e4ae9e1c833c8785644c1
Deleted: sha256:2dc39ba059dcd42ade30aae30147b5692777ba9ff0779a62ad93a74de02e3e1f
Deleted: sha256:7f5cbd8cc787c8d628630756bcc7240e6c96b876c2882e6fc980a8b60cdfa274
3、执行docker image ls命令查看镜像是否成功删除，这里观察到，已成功删除。
root@zq-virtual-machine:/var/lib/docker# docker image ls
REPOSITORY TAG IMAGE ID CREATED SIZE
4、执行docker image pull ubuntu@sha256:20fa2d7bb4de7723f542be5923b06c4d704370f0390e4ae9e1c833c8785644c1命令根据摘要再次拉取ubuntu:latest镜像。
root@zq-virtual-machine:/var/lib/docker# docker image pull ubuntu@sha256:20fa2d7bb4de7723f542be5923b06c4d704370f0390e4ae9e1c833c8785644c1
docker.io/library/ubuntu@sha256:20fa2d7bb4de7723f542be5923b06c4d704370f0390e4ae9e1c833c8785644c1: Pulling from library/ubuntu
2b55860d4c66: Pull complete
Digest: sha256:20fa2d7bb4de7723f542be5923b06c4d704370f0390e4ae9e1c833c8785644c1
Status: Downloaded newer image for ubuntu@sha256:20fa2d7bb4de7723f542be5923b06c4d704370f0390e4ae9e1c833c8785644c1
1.9 删除镜像¶
1、执行docker image pull ubuntu:latest命令下载一组镜像-ubuntu:latest。
root@zq-virtual-machine:/var/lib/docker# docker image pull ubuntu:latest
latest: Pulling from library/ubuntu
2b55860d4c66: Pull complete
Digest: sha256:20fa2d7bb4de7723f542be5923b06c4d704370f0390e4ae9e1c833c8785644c1
Status: Downloaded newer image for ubuntu:latest
2、执行docker image ls -q命令获取镜像ID。
root@zq-virtual-machine:/var/lib/docker# docker image ls -q
2dc39ba059dc
3、执行docker image rm $(docker image ls -q) -f命令删除本地系统中的全部镜像。
root@zq-virtual-machine:/var/lib/docker# docker image rm $(docker image ls -q) -f
4、执行docker image ls命令验证镜像是否删除，这里观察到，镜像已成功删除。
root@zq-virtual-machine:/var/lib/docker# docker image ls
REPOSITORY TAG IMAGE ID CREATED SIZE
1.10 查看构建镜像执行历史指令¶
1、执行docker image history web:latest命令查看构建镜像执行了哪些历史指令。
root@zq-virtual-machine:/home/zq/Desktop/psweb# docker image history web:latest
IMAGE CREATED CREATED BY SIZE COMMENT
683c55e54235 2 hours ago /bin/sh -c #(nop) ENTRYPOINT ["node" "./app… 0B
4f4a2d392749 2 hours ago /bin/sh -c #(nop) EXPOSE 8080 0B
a622f45f36d3 2 hours ago /bin/sh -c npm install 27MB
f73bb626a9b7 2 hours ago /bin/sh -c #(nop) WORKDIR /src 0B
29d1736dc769 2 hours ago /bin/sh -c #(nop) COPY dir:310d2a161b2d2b7a1… 42.1kB
20d2ab48de19 2 hours ago /bin/sh -c apk add --update nodejs npm curl 54.3MB
2e2dc063771c 2 hours ago /bin/sh -c #(nop) LABEL maintainer=nigelpou… 0B
9c6f07244728 8 weeks ago /bin/sh -c #(nop) CMD ["/bin/sh"] 0B
<missing> 8 weeks ago /bin/sh -c #(nop) ADD file:2a949686d9886ac7c… 5.54MB
2、针对以上内容，有几点需要注意: (1)每行内容对应一条指令，顺序是自下而上，CREATED BY 具体展示了当前行具体对应Dockerfile中哪些指令。 (2)SIZE不为零的指令会新建镜像层，对应FROM、RUN和COPY指令。SIZE为零的指令只是新增了元数据信息，不会新建镜像层。
1.11 镜像打标签(不覆盖原来的标签)¶
命令格式为docker image tag <当前的标签> <新标签> 1、执行docker image tag web:latest jeckjohn/web:latest命令为当前镜像重新打一个标签。
zq@zq-virtual-machine:~/Desktop/psweb$ docker image tag web:latest jeckjohn/web:latest
2、继续执行docker image ls命令查看标签重打是否成功。这里观察到，标签重打成功。
zq@zq-virtual-machine:~/Desktop/psweb$ docker image ls
REPOSITORY TAG IMAGE ID CREATED SIZE
jeckjohn/web latest 683c55e54235 37 minutes ago 87MB
web latest 683c55e54235 37 minutes ago 87MB
1.12 推送镜像到镜像库¶
1、继续执行docker image push jeckjohn/web:latest命令将该镜像推送到Docker Hub上。
zq@zq-virtual-machine:~/Desktop/psweb$ docker image push jeckjohn/web:latest
The push refers to repository [docker.io/jeckjohn/web]
32afb898c296: Pushed
7b222b64804f: Pushed
e0eb8cd31e9f: Pushed
994393dc58e7: Mounted from library/alpine
latest: digest: sha256:0d02bf3f3a6a16c98235f3d1e6d3e2501f34665e009dea3b0fd69cfb592a519d size: 1161
1.13 构建新镜像¶
1、在Dockerfile所在文件夹视图执行docker image build -t web:latest . 命令构建生成一个名为web:latest的镜像，其中命令最后的点代表Docker在进行构建的时候，使用当前目录作为构建上下文。其中-t参数指的是给镜像打标签，使用-f参数指定Dockfile的路径和名称。
zq@zq-virtual-machine:~/Desktop/psweb$ docker image build -t web:latest .
2、执行docker image ls命令查看镜像是否下载成功。这里观察到，镜像已成功下载。
zq@zq-virtual-machine:~/Desktop/psweb$ docker image ls
REPOSITORY TAG IMAGE ID CREATED SIZE
web latest 683c55e54235 2 minutes ago 87MB
3、构建新镜像过程如下: (1)运行临时容器 (2)在该容器运行Dockerfile中的指令 (3)将指令运行的结果保存为一个新的镜像层 (4)删除临时容器
1.14 合并镜像¶
1、执行docker image build ubuntu:latest--squash命令创建一个合并的镜像。
root@zq-virtual-machine:~# docker image build ubuntu:latest--squash
二、Docker容器相关操作¶
2.1 启动容器¶
1、执行docker container run -it ubuntu:latest /bin/bash命令启动容器。其中-it参数是用来告诉Docker开启容器的交互模式并将读者当前的Shell连接到容器终端，并运行Bash Shell作为其应用。
root@zq-virtual-machine:~# docker container run -it ubuntu:latest /bin/bash
root@19aa9b16e05f:/#
2、执行ps -elf命令查看当前正在运行的全部进程。
root@19aa9b16e05f:/# ps -elf
F S UID PID PPID C PRI NI ADDR SZ WCHAN STIME TTY TIME CMD
4 S root 1 0 0 80 0 - 1156 do_wai 01:21 pts/0 00:00:00 /bin/bash
0 R root 9 1 0 80 0 - 1765 - 01:24 pts/0 00:00:00 ps -elf
说明:命令输出中展示的ps-elf进程存在一定的误导，因为这个程序在ps命令退出后就结束了。
3、针对以上进程进行说明如下
| 进程 | 代表进程 | 进程说明 |
|---|---|---|
| PID 1 | /bin/bash | 该进程通过docker container run命令来通知容器运行的 |
| PID 9 | ps -elf | 查看当前运行中进程所使用的命令/程序 |
2.2 退出容器¶
1、按Ctrl+PQ键退出容器。
root@19aa9b16e05f:/# root@zq-virtual-machine:~#
root@zq-virtual-machine:~#
2.3 连接到运行中的容器¶
1、执行docker container ls命令查看Docker主机上运行中容器名称。这里观察到容器名称为suspicious_black和elated_kare。
root@zq-virtual-machine:~# docker container ls
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
a80744307532 ubuntu:latest "/bin/bash" 2 minutes ago Up 2 minutes suspicious_black
19aa9b16e05f ubuntu:latest "/bin/bash" 20 minutes ago Up 20 minutes elated_kare
2、执行docker container exec -it suspicious_black bash命令将Shell连接到一个运行中的容器终端。这里以suspicious_black为例。观察到，连接成功。
root@zq-virtual-machine:~# docker container exec -it suspicious_black bash
root@a80744307532:/#
3、按Ctrl+PQ键退出容器。
root@a80744307532:/# read escape sequence
root@zq-virtual-machine:~#
2.4 停止并杀死容器¶
1、执行docker container stop suspicious_black命令停止容器。
root@zq-virtual-machine:~# docker container stop suspicious_black
suspicious_black
2、执行docker container rm suspicious_black命令杀死容器。
root@zq-virtual-machine:~# docker container rm suspicious_black
suspicious_black
3、执行docker container ls -a命令查看Docker所有容器(包括停止状态的)。其中-a参数的作用是让Docker列出所有的，包括不在运行状态的。
root@zq-virtual-machine:~# docker container ls -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
2.5 直接杀死容器¶
1、执行docker container rm percy -f命令直接杀死容器。
root@zq-virtual-machine:~# docker container rm percy -f
percy
2、执行docker container rm $(docker container ls -aq) -f命令直接杀死全部容器(包括不在用的)。其中-a参数代表全部，-q参数代表仅显示容器 ID。
root@zq-virtual-machine:~# docker container rm $(docker container ls -aq) -f
98cf414f8e0d
2.6 不同重启策略实现容器自我修复¶
2.6.1 always策略¶
1、执行docker container run --name neversaydie -it --restart always alpine sh命令创建名为neversaydie的容器，其中-it参数是用来告诉Docker开启容器的交互模式并将读者当前的Shell连接到容器终端。--restart always指定重启策略为always策略。
root@zq-virtual-machine:~# docker container run --name neversaydie -it --restart always alpine sh
2、等待几秒后输入exit命令。
/ #
/ # exit
3、执行docker container ls命令查看容器信息，观察到，容器创建时间为23秒前，但却在9s前启动，这是因为在容器输入退出命令后，容器被杀死后docker又重启了该容器。
root@zq-virtual-machine:~# docker container ls
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
06bb3d0eccb4 alpine "sh" 23 seconds ago Up 9 seconds neversaydie
2.6.2 unless-stopped策略¶
1、执行命令分别创建两个名为always和unless-stopped的新容器。
root@zq-virtual-machine:~# docker container run -d --name always --restart unless-stopped alpine sleep 1d
root@zq-virtual-machine:~# docker container run -d --name unless-stopped --restart unless-stopped alpine sleep 1d
root@zq-virtual-machine:~# docker container ls
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
1e6dbeb1a598 alpine "sleep 1d" 10 seconds ago Up 9 seconds unless-stopped
ec0cca8a3bd7 alpine "sleep 1d" About a minute ago Up About a minute always
2、执行docker container stop always unless-stopped always命令停止两个容器。
root@zq-virtual-machine:~# docker container stop always unless-stopped
always
unless-stopped
3、执行systemctl restart docker命令重启docker。
root@zq-virtual-machine:~# systemctl restart docker
4、Docker重启成功后，执行docker container ls -a命令检查两个容器状态。观察到启动时指定--restart unless-stopped没有重启。
root@zq-virtual-machine:~# docker container ls -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
1e6dbeb1a598 alpine "sleep 1d" 2 minutes ago Exited (137) 50 seconds ago unless-stopped
ec0cca8a3bd7 alpine "sleep 1d" 3 minutes ago Up 5 seconds always
2.7 显示容器配置细节和运行信息¶
1、执行docker container inspect命令显示容器配置细节和运行信息。
root@zq-virtual-machine:~# docker container inspect