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目录
一、认识docer
传统虚拟机方式
拥有完整内核和相应的库才能安装需要的app，模拟了一台完整的电脑
缺点：
- 资源占用多
- 冗余步骤多
- 启动慢
- 资源公用，某个设置出问题可能导致多个应用出问题
docer容器化技术
优点：
- 容器内的应用直接运行在宿主机的内核，容器没有自己的内核
- 每个容器内有一个属于自己的文件系统互不影响，容器之间相互隔离互不影响
- 打包镜像发布测试，一键运行
- 更便捷的升级和扩容
- 容器化之后，开发和测试环境高度一致
- 更高效的计算资源利用，Docer是内核级别的虚拟化，可以在一个物理机上运行多个容器实例，服务器性能可以压榨到极致
镜像（image）容器（container）仓库（repository）
流程：客户端启动docer里的一个容器，容器要从服务器上下载
二、在阿里云服务器上配置Docker
需要购买一个阿里云服务器，活动99一年的就够了，需要分配外网ipv4地址
步骤（参考docker官网文档）
1、卸载旧的docker
sudo yum remove docker \ docker-client \ docker-client-latest \ docker-common \ docker-latest \ docker-latest-logrotate\ docker-logrotate \ docker-engine 2、添加仓库
sudo yum install -y yum-utils 3、设置镜像仓库为阿里云国内源
sudo yum-config-manager --add-repo \ http://mirrors.aliyun.com/dockerce/linux/centos/docker-ce.repo 4、更新索引
yum makecache fast 5、安装docker
sudo yum install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin 6、启动docker
sudo systemctl start docker 7、判断是否启动成功
docker version sudo docker run hello-world hello-word程序的执行流程
8、配置阿里云镜像加速
sudo mkdir -p /etc/docker sudo tee /etc/docker/daemon.json <<-'EOF' { "registry-mirrors": ["https://rpu0hzw5.mirror.aliyuncs.com"] } EOFEO sudo systemctl daemon-reload sudo systemctl restart docker 三、底层原理
Docker是一个Client-Server结构的系统，Docker的守护进程运行在主机上，通过Socket从客户端访问，DockerServer接受到Docker-Client的指令，就会执行这个命令
Docker为什么比VM快
- Docker有着比虚拟机更少的抽象层
- Docker利用的是宿主机的内核,vm需要的是Guest OS（Guest Operating System 指在虚拟化环境中运行的操作系统）
所以，新建一个容器的时候，docker不需要和虚拟机一样重新加载一个操作系统的内核，直接利用宿主机的操作系统内核
4、常用命令
（1）Docker中常见镜像命令
查看帮助文档 docker [命令] --help
[root@aliyun_docker ~]# docker top --help Usage: docker top CONTAINER [ps OPTIONS] Display the running processes of a container Aliases: docker container top, docker top 搜索镜像
docker search
[root@iZ2vc3j8qdus28heb8myw2Z ~]# docker search mysql NAME DESCRIPTION STARS OFFICIAL mysql MySQL is a widely used, open-source relation… 15008 [OK] mariadb MariaDB Server is a high performing open sou… 5722 [OK] 下载镜像
docker pull
[root@iZ2vc3j8qdus28heb8myw2Z ~]# docker pull mysql Using default tag: latest#如果不写tag默认下载最新版本 latest: Pulling from library/mysql 72a69066d2fe: Pull complete 93619dbc5b36: Pull complete 99da31dd6142: Pull complete 626033c43d70: Pull complete 37d5d7efb64e: Pull complete ac563158d721: Pull complete d2ba16033dad: Pull complete 688ba7d5c01a: Pull complete 00e060b6d11d: Pull complete 1c04857f594f: Pull complete 4d7cfa90e6ea: Pull complete e0431212d27d: Pull complete Digest: sha256:e9027fe4d91c0153429607251656806cc784e914937271037f7738bd5b8e7709 Status: Downloaded newer image for mysql:latest docker.io/library/mysql:latest 当下载同应用不同版本只会下载没有的部分，原有的可以公用的部分不会重复下载，节省空间
[root@iZ2vc3j8qdus28heb8myw2Z ~]# docker pull mysql:5.7 5.7: Pulling from library/mysql 72a69066d2fe: Already exists 93619dbc5b36: Already exists 99da31dd6142: Already exists 626033c43d70: Already exists 37d5d7efb64e: Already exists ac563158d721: Already exists d2ba16033dad: Already exists 0ceb82207cd7: Pull complete 37f2405cae96: Pull complete e2482e017e53: Pull complete 70deed891d42: Pull complete Digest: sha256:f2ad209efe9c67104167fc609cca6973c8422939491c9345270175a300419f94 Status: Downloaded newer image for mysql:5.7 docker.io/library/mysql:5.7 查看所有镜像
docker images
[root@iZ2vc3j8qdus28heb8myw2Z ~]# docker images REPOSITORY TAG IMAGE ID CREATED SIZE hello-world latest d2c94e258dcb 11 months ago 13.3kB mysql 5.7 c20987f18b13 2 years ago 448MB mysql latest 3218b38490ce 2 years ago 516MB 通过IMAGE ID 删除 image，加空格可以删除多个，
dock rmi -f $(docker images -aq)组合命令删除全部容器
[root@iZ2vc3j8qdus28heb8myw2Z ~]# docker rmi -f 3218b38490ce Untagged: mysql:latest Untagged: mysql@sha256:e9027fe4d91c0153429607251656806cc784e914937271037f7738bd5b8e7709 Deleted: sha256:3218b38490cec8d31976a40b92e09d61377359eab878db49f025e5d464367f3b Deleted: sha256:aa81ca46575069829fe1b3c654d9e8feb43b4373932159fe2cad1ac13524a2f5 Deleted: sha256:0558823b9fbe967ea6d7174999be3cc9250b3423036370dc1a6888168cbd224d Deleted: sha256:a46013db1d31231a0e1bac7eeda5ad4786dea0b1773927b45f92ea352a6d7ff9 Deleted: sha256:af161a47bb22852e9e3caf39f1dcd590b64bb8fae54315f9c2e7dc35b025e4e3 Deleted: sha256:feff1495e6982a7e91edc59b96ea74fd80e03674d92c7ec8a502b417268822ff [root@iZ2vc3j8qdus28heb8myw2Z ~]# （2）Docker中常见容器命令
有了镜像才可以创建容器，
新建容器并启动
docker run [可选参数] image
#可选参数说明
–name = “Name” 容器名字,用来区分容器 tomcat01 tomcat02，用来区分容器
-d 后台方式运行（如果要后台运行必须要有一个前台进程，容器启动后发现自己没有提供服务就会立刻停止）
-it 使用交互方式运行，进入容器查看内容
-p 指定容器的端口 -P 8080:8080
-p ip:主机端口:容器端口
-p 主机端口:容落端口 (常用)
-p 容器端口
容器端口
-p 随机指定端口
[root@aliyun_docker ~]# docker images REPOSITORY TAG IMAGE ID CREATED SIZE hello-world latest d2c94e258dcb 11 months ago 13.3kB mysql 5.7 c20987f18b13 2 years ago 448MB centos latest 5d0da3dc9764 2 years ago 231MB [root@aliyun_docker ~]# docker run -it centos /bin/bash [root@a790c5209310 /]# 可以发现进入容器后主机名称变了
退出（按三个键CTRL+p+q，退出不关闭）
[root@aliyun_docker ~]# docker run -it centos /bin/bash [root@b8630535a0c9 /]# [root@aliyun_docker ~]# [root@aliyun_docker ~]# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES b8630535a0c9 centos "/bin/bash" 43 seconds ago Up 43 seconds keen_kepler [root@b8630535a0c9 /]# exit 查看当前正在运行/运行过的容器（加 -a）
[root@aliyun_docker ~]# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES [root@aliyun_docker ~]# docker ps -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES a790c5209310 centos "/bin/bash" 3 minutes ago Exited (0) About a minute ago funny_brahmagupta 2321a478186b hello-world "/hello" 4 hours ago Exited (0) 4 hours ago eager_pascal [root@aliyun_docker ~]# 只显示编号 -q
[root@aliyun_docker ~]# docker ps -aq a790c5209310 2321a478186b 删除容器
docker rm 容器id #删除指定容器正在运行的不能删除（加-f） docker rm -f $(docker ps -aq) #删除所有 docker ps -a -q|xargs docker rm #通过管道删除 [root@aliyun_docker ~]# docker rm b8630535a0c9 Error response from daemon: cannot remove container "/keen_kepler": container is running: stop the container before removing or force remove 启动和停止
docker start 容器id #启动容器 docker restart 容器id #重启容器 docker stop 容器id #停止当前正在运行的容器 docker kill 容器id #强制停止当前容器（实例仍然存在） （3）日志查看命令
写一段shell脚本
[root@aliyun_docker ~]# docker run -d centos /bin/bash -c "while true;do echo xiakucao;sleep 1;done" 22249409fb3c95efe4ad51637a6340abb5b5c212183531a4ee261444aef130cf [root@aliyun_docker ~]# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 22249409fb3c centos "/bin/bash -c 'while…" 5 seconds ago Up 3 seconds jolly_hodgkin b8630535a0c9 centos "/bin/bash" 29 minutes ago Up 29 minutes keen_kepler [root@aliyun_docker ~]# 显示指定行数的日志
[root@aliyun_docker ~]# docker logs -f -t --tail 10 22249409fb3c 2024-04-18T14:15:44.419231635Z xiakucao 2024-04-18T14:15:45.421276341Z xiakucao 2024-04-18T14:15:46.423269443Z xiakucao 2024-04-18T14:15:47.425443716Z xiakucao 2024-04-18T14:15:48.427495542Z xiakucao 2024-04-18T14:15:49.429472406Z xiakucao 2024-04-18T14:15:50.431600097Z xiakucao 2024-04-18T14:15:51.434124367Z xiakucao 2024-04-18T14:15:52.436540492Z xiakucao 2024-04-18T14:15:53.438632432Z xiakucao 2024-04-18T14:15:54.441042791Z xiakucao 2024-04-18T14:15:55.443170520Z xiakucao 2024-04-18T14:15:56.445296720Z xiakucao 2024-04-18T14:15:57.447415752Z xiakucao 2024-04-18T14:15:58.449874664Z xiakucao 2024-04-18T14:15:59.451981852Z xiakucao ^Z [3]+ Stopped docker logs -f -t --tail 10 22249409fb3c [root@aliyun_docker ~]# 查看容器中进程信息
[root@aliyun_docker ~]# docker top 22249409fb3c UID PID PPID C STIME TTY TIME CMD root 1769 1748 0 22:14 ? 00:00:00 /bin/bash -c while true;do echo xiakucao;sleep 1;done root 2122 1769 0 22:19 ? 00:00:00 /usr/bin/coreutils --coreutils-prog-shebang=sleep /usr/bin/sleep 1 查看镜像的元数据
docker inspect
可以看到IMAGE ID截取的是部分ID
[root@aliyun_docker ~]# docker inspect 22249409fb3c [ { "Id": "22249409fb3c95efe4ad51637a6340abb5b5c212183531a4ee261444aef130cf", "Created": "2024-04-18T14:14:13.991971662Z", "Path": "/bin/bash", "Args": [ "-c", "while true;do echo xiakucao;sleep 1;done" ], "State": { "Status": "running", "Running": true, "Paused": false, "Restarting": false, "OOMKilled": false, "Dead": false, "Pid": 1769, "ExitCode": 0, "Error": "", "StartedAt": "2024-04-18T14:14:14.22346875Z", "FinishedAt": "0001-01-01T00:00:00Z" }, "Image": "sha256:5d0da3dc976460b72c77d94c8a1ad043720b0416bfc16c52c45d4847e53fadb6", "ResolvConfPath": "/var/lib/docker/containers/22249409fb3c95efe4ad51637a6340abb5b5c212183531a4ee261444aef130cf/resolv.conf", "HostnamePath": "/var/lib/docker/containers/22249409fb3c95efe4ad51637a6340abb5b5c212183531a4ee261444aef130cf/hostname", "HostsPath": "/var/lib/docker/containers/22249409fb3c95efe4ad51637a6340abb5b5c212183531a4ee261444aef130cf/hosts", "LogPath": "/var/lib/docker/containers/22249409fb3c95efe4ad51637a6340abb5b5c212183531a4ee261444aef130cf/22249409fb3c95efe4ad51637a6340abb5b5c212183531a4ee261444aef130cf-json.log", "Name": "/jolly_hodgkin", "RestartCount": 0, "Driver": "overlay2", "Platform": "linux", "MountLabel": "", "ProcessLabel": "", "AppArmorProfile": "", "ExecIDs": null, "HostConfig": { "Binds": null, "ContainerIDFile": "", "LogConfig": { "Type": "json-file", "Config": {} }, "NetworkMode": "default", "PortBindings": {}, "RestartPolicy": { "Name": "no", "MaximumRetryCount": 0 }, "AutoRemove": false, "VolumeDriver": "", "VolumesFrom": null, "ConsoleSize": [ 31, 102 ], "CapAdd": null, "CapDrop": null, "CgroupnsMode": "host", "Dns": [], "DnsOptions": [], "DnsSearch": [], "ExtraHosts": null, "GroupAdd": null, "IpcMode": "private", "Cgroup": "", "Links": null, "OomScoreAdj": 0, "PidMode": "", "Privileged": false, "PublishAllPorts": false, "ReadonlyRootfs": false, "SecurityOpt": null, "UTSMode": "", "UsernsMode": "", "ShmSize": 67108864, "Runtime": "runc", "Isolation": "", "CpuShares": 0, "Memory": 0, "NanoCpus": 0, "CgroupParent": "", "BlkioWeight": 0, "BlkioWeightDevice": [], "BlkioDeviceReadBps": [], "BlkioDeviceWriteBps": [], "BlkioDeviceReadIOps": [], "BlkioDeviceWriteIOps": [], "CpuPeriod": 0, "CpuQuota": 0, "CpuRealtimePeriod": 0, "CpuRealtimeRuntime": 0, "CpusetCpus": "", "CpusetMems": "", "Devices": [], "DeviceCgroupRules": null, "DeviceRequests": null, "MemoryReservation": 0, "MemorySwap": 0, "MemorySwappiness": null, "OomKillDisable": false, "PidsLimit": null, "Ulimits": [], "CpuCount": 0, "CpuPercent": 0, "IOMaximumIOps": 0, "IOMaximumBandwidth": 0, "MaskedPaths": [ "/proc/asound", "/proc/acpi", "/proc/kcore", "/proc/keys", "/proc/latency_stats", "/proc/timer_list", "/proc/timer_stats", "/proc/sched_debug", "/proc/scsi", "/sys/firmware", "/sys/devices/virtual/powercap" ], "ReadonlyPaths": [ "/proc/bus", "/proc/fs", "/proc/irq", "/proc/sys", "/proc/sysrq-trigger" ] }, "GraphDriver": { "Data": { "LowerDir": "/var/lib/docker/overlay2/46c4ebdbc616cb8d052b73a0b47a03dbef18a7f1d0ad17346a982c658d5660a0-init/diff:/var/lib/docker/overlay2/cfef35f2fd2430f54798e47b3ce3056bbd96fa29637ba2fa8144daa1c925a355/diff", "MergedDir": "/var/lib/docker/overlay2/46c4ebdbc616cb8d052b73a0b47a03dbef18a7f1d0ad17346a982c658d5660a0/merged", "UpperDir": "/var/lib/docker/overlay2/46c4ebdbc616cb8d052b73a0b47a03dbef18a7f1d0ad17346a982c658d5660a0/diff", "WorkDir": "/var/lib/docker/overlay2/46c4ebdbc616cb8d052b73a0b47a03dbef18a7f1d0ad17346a982c658d5660a0/work" }, "Name": "overlay2" }, "Mounts": [], "Config": { "Hostname": "22249409fb3c", "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/bash", "-c", "while true;do echo xiakucao;sleep 1;done" ], "Image": "centos", "Volumes": null, "WorkingDir": "", "Entrypoint": null, "OnBuild": null, "Labels": { "org.label-schema.build-date": "20210915", "org.label-schema.license": "GPLv2", "org.label-schema.name": "CentOS Base Image", "org.label-schema.schema-version": "1.0", "org.label-schema.vendor": "CentOS" } }, "NetworkSettings": { "Bridge": "", "SandboxID": "b02c97f64a8992dc0f322a5acc0d2871115ff1654e680a06bdb86591659fef10", "SandboxKey": "/var/run/docker/netns/b02c97f64a89", "Ports": {}, "HairpinMode": false, "LinkLocalIPv6Address": "", "LinkLocalIPv6PrefixLen": 0, "SecondaryIPAddresses": null, "SecondaryIPv6Addresses": null, "EndpointID": "daa0dad6de8bfdaab015d01972c6e0e7ff1518b23d839a9407c81b15c14d3564", "Gateway": "172.17.0.1", "GlobalIPv6Address": "", "GlobalIPv6PrefixLen": 0, "IPAddress": "172.17.0.3", "IPPrefixLen": 16, "IPv6Gateway": "", "MacAddress": "02:42:ac:11:00:03", "Networks": { "bridge": { "IPAMConfig": null, "Links": null, "Aliases": null, "MacAddress": "02:42:ac:11:00:03", "NetworkID": "f9a1764ef63ab36cfd232cf326edc32a337b8722c30a9964659b044b0fecf5c4", "EndpointID": "daa0dad6de8bfdaab015d01972c6e0e7ff1518b23d839a9407c81b15c14d3564", "Gateway": "172.17.0.1", "IPAddress": "172.17.0.3", "IPPrefixLen": 16, "IPv6Gateway": "", "GlobalIPv6Address": "", "GlobalIPv6PrefixLen": 0, "DriverOpts": null, "DNSNames": null } } } } ] （4）进入容器的命令与拷贝命令
exec进入容器用bash命令，（run是创建并进入，exec仅进入容器）
exec进入容器后会开启一个新的终端，可以在里面进行操作
[root@aliyun_docker ~]# docker exec -it 22249409fb3c /bin/bash [root@22249409fb3c /]# attach命令 进入正在执行的终端，不会启动新的进程
[root@aliyun_docker ~]# docker attach 22249409fb3c xiakucao xiakucao xiakucao xiakucao 从容器内拷贝文件到主机上
只要容器还在，容器内的文件就不会消失
[root@aliyun_docker ~]# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 0eb80da8ce30 centos "/bin/bash" About a minute ago Up About a minute agitated_bhaskara [root@aliyun_docker ~]# docker attach 0eb80da8ce30 [root@0eb80da8ce30 home]# cd /home [root@0eb80da8ce30 home]# ls [root@0eb80da8ce30 home]# touch test.java [root@0eb80da8ce30 home]# exit exit [root@aliyun_docker ~]# docker ps -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 0eb80da8ce30 centos "/bin/bash" 2 minutes ago Exited (0) 6 seconds ago agitated_bhaskara [root@aliyun_docker ~]# docer cp 0eb80da8ce30:/home/test.java /home -bash: docer: command not found [root@aliyun_docker ~]# docker cp 0eb80da8ce30:/home/test.java /home Successfully copied 1.54kB to /home [root@aliyun_docker ~]# 小结
四、部署容器
部署nginx
-d后台运行
-name 给容器命名
-p 宿主机端口：容器内部端口
[root@aliyun_docker ~]# docker run -d --name nginx01 -p 3389:80 nginx b42c715ebae889c6d180b18305f523d2abefe33f11685b3e7354ea1fd776b86e 端口原理图
测试端口
[root@aliyun_docker ~]# curl localhost:3389 <!DOCTYPE html> <html> <head> <title>Welcome to nginx!</title> <style> html { color-scheme: light dark; } 五、dockerfile命令
DockerFile是什么
DockerFile：构建文件，定义了一切的步骤，源代码
DockerImages：通过DockerFile构建生成的镜像，最终发布和运行的产品
Docker容器：容器就是镜像运行起来提供服务器
常见命令
tips:
- 用ADD命令添加的文件会自动解压
自制一个centos镜像
scratch是一个特殊的空白镜像，它是Docker官方提供的最小的镜像，不包含任何操作系统或文件系统。它可以作为基础镜像，用于构建定制化的镜像。Docker Hub中大部分镜像都是从这个基础镜像过来的 FROM scratch没然后配置需要的软件和配置来构建
创建的镜像版本尽量和宿主机匹配我的云服务器是centos7
FROM centos:7 MAINTAINER xiakucao<1844966859@qq.com> ENV MYPATH /usr/local WORKDIR $MYPATH #默认进入根目录 RUN yum -y install vim RUN yum -y install net-tools EXPOSE 80 CMD echo $MYPATH CMD echo "-------end--------" CMD /bin/bash #注意有个点 [root@aliyun_docker dockerfile]# vim mydockerfile-centos [root@aliyun_docker dockerfile]# docker build -f mydockerfile-centos -t mycentos:0.2 . [+] Building 54.7s (8/8) FINISHED 查看镜像的构建过程
[root@aliyun_docker dockerfile]# docker history 7e0c8c0fb962 IMAGE CREATED CREATED BY SIZE COMMENT 7e0c8c0fb962 3 minutes ago CMD ["/bin/sh" "-c" "/bin/bash"] 0B buildkit.dockerfile.v0 <missing> 3 minutes ago CMD ["/bin/sh" "-c" "echo \"-------end------… 0B buildkit.dockerfile.v0 <missing> 3 minutes ago CMD ["/bin/sh" "-c" "echo $MYPATH"] 0B buildkit.dockerfile.v0 <missing> 3 minutes ago EXPOSE map[80/tcp:{}] 0B buildkit.dockerfile.v0 <missing> 3 minutes ago RUN /bin/sh -c yum -y install net-tools # bu… 212MB buildkit.dockerfile.v0 <missing> 3 minutes ago RUN /bin/sh -c yum -y install vim # buildkit 301MB buildkit.dockerfile.v0 <missing> 4 minutes ago WORKDIR /usr/local 0B buildkit.dockerfile.v0 <missing> 4 minutes ago ENV MYPATH=/usr/local 0B buildkit.dockerfile.v0 <missing> 4 minutes ago MAINTAINER xiakucao<1844966859@qq.com> 0B buildkit.dockerfile.v0 <missing> 2 years ago /bin/sh -c #(nop) CMD ["/bin/bash"] 0B <missing> 2 years ago /bin/sh -c #(nop) LABEL org.label-schema.sc… 0B <missing> 2 years ago /bin/sh -c #(nop) ADD file:b3ebbe8bd304723d4… 204MB [root@aliyun_docker dockerfile]# 学习记录
2024/4/19 p30
https://www.bilibili.com/video/BV1og4y1q7M4
