学自狂神
Docker安装
Docker的基本组成
镜像（image）：
docker镜像就好比是一个模板，可以通过这个模板来创建容器服务，tomcat镜像===>run==>toncat01容器（提供服务器），
通过这个镜像可以创建多个容器（最终服务运行或者项目运行就是在容器中）。
容器（container）：
Docker利用容器技术，独立运行一个或者一个组应用，通过镜像来创建的。
启动，停止，删除，基本命令！
目前就可以把这个容器理解为就是一个简易的Linux系统
仓库(repository）：
仓库就是存放镜像的地方！
仓库分为公有仓库和私有仓库！
Docker Hub（默认是国外的）
阿里云、腾讯云、华为云......都有容器服务器（配置镜像加速）！
安装步骤
官网：Install Docker Engine on CentOS | Docker Documentation
帮助文档：
#1、卸载旧版本 yum remove docker \ docker-client \ docker-client-latest \ docker-common \ docker-latest \ docker-latest-logrotate \ docker-logrotate \ docker-engine #2、需要的安装包 yum install -y yum-utils #3、设置镜像的仓库 yum-config-manager \ --add-repo \ https://download.docker.com/linux/centos/docker-ce.repo #默认是国外的！ #阿里云镜像 yum-config-manager \ --add-repo \ http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo # 更新yum软件包索引 yum makecache fast #4、安装docker docker-ce 社区版 ee 企业版 yum install docker-ce docker-ce-cli containerd.io #5、启动docker systemctl start docker #6、使用docker version查看是否安装成功
#7、hello-world docker run hello-world
#8、查看一下下载的这个hello-world镜像 [root@iZuf60urtgz7708wda7blnZ ~]# docker images REPOSITORY TAG IMAGE ID CREATED SIZE hello-world latest feb5d9fea6a5 6 months ago 13.3kB
卸载docker
#1、卸载依赖 yum remove docker-ce docker-ce-cli containerd.io #2、删除资源 rm -rf /var/lib/docker # /var/lib/docker docker的默认工作路径
阿里云镜像加速
1、登录阿里云 找到容器与镜像服务
2、找到镜像加速地址
3、配置使用
sudo mkdir -p /etc/docker
sudo tee /etc/docker/daemon.json <<-'EOF'
{
"registry-mirrors": ["https://yv7fgssm.mirror.aliyuncs.com"]
}
EOF
sudo systemctl daemon-reload
sudo systemctl restart docker
回顾HelloWorld流程
底层原理
Docker是怎么工作的？
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接收到Docker-Client，就会执行或者命令！
Docker为什么比VM快？
1、Docker有着比虚拟机更少的抽象层。
2、Docker利用的是宿主机的内核，VM需要的是Guest OS。
所以说，新建一个容器的时候，docker不需要像虚拟机一样重新加载一个操作系统内核，避免引导。虚拟机是加载Guest OS，分钟级别的，而docker利用的是宿主机对的操作系统，省略了这个复杂的过程，秒级。
Docker的常用命令
帮助命令
docker version #显示docker的版本信息 docker info 信息 # docker 命令 --info
帮助文档的地址：Docker run reference | Docker Documentation
镜像命令
docker images 查看所有本地的主机上的镜像
[root@iZuf60urtgz7708wda7blnZ ~]# docker images REPOSITORY TAG IMAGE ID CREATED SIZE hello-world latest feb5d9fea6a5 6 months ago 13.3kB # 解释 REPOSITORY 镜像的仓库源 TAG 镜像的标签 IMAGE ID 镜像的id CREATED 镜像的创建时间 SIZE 镜像的大小 # 可选项 -a, --all # 列出所有镜像 -q, --quiet # 只显示镜像的id
docker search 搜索镜像
[root@iZuf60urtgz7708wda7blnZ ~]# docker search mysql NAME DESCRIPTION STARS OFFICIAL AUTOMATED mysql MySQL is a widely used, open-source relation… 12350 [OK] mariadb MariaDB Server is a high performing open sou… 4753 [OK] # 可选项，通过收藏来过滤 --filter=STARS=3000 # 搜索出来的镜像就是STAR大于3000的 [root@iZuf60urtgz7708wda7blnZ ~]# docker search mysql --filter=STARS=3000 NAME DESCRIPTION STARS OFFICIAL AUTOMATED mysql MySQL is a widely used, open-source relation… 12350 [OK] mariadb MariaDB Server is a high performing open sou… 4753 [OK]
docker pull 下载镜像
# 下载镜像 docker pull 镜像名[:tag] [root@iZuf60urtgz7708wda7blnZ ~]# docker pull mysql Using default tag: latest # 如果不写tag 默认就是latest latest: Pulling from library/mysql 72a69066d2fe: Pull complete # 分层下载，docker image的核心 联合文件系统 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 # 签名 Status: Downloaded newer image for mysql:latest docker.io/library/mysql:latest # 真实地址 # 等价 docker pull mysql docker pull mysql docker.io/library/mysql:latest # 指定版本下载 [root@iZuf60urtgz7708wda7blnZ ~]# 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
docker rmi 删除镜像
[root@iZuf60urtgz7708wda7blnZ ~]# docker rmi -f 镜像id # 删除指定的镜像 [root@iZuf60urtgz7708wda7blnZ ~]# docker rmi -f 镜像id 镜像id 镜像id # 删除指定的镜像 [root@iZuf60urtgz7708wda7blnZ ~]# docker rmi -f $(docker images -aq) # 删除全部的镜像
容器命令
说明：我们有了镜像才可以创建容器，linux 下载一个centOS镜像来测试学习
docker pull centos
新建容器并启动
docker run [可选参数] image # 参数说明 --name="Name" 容器名字 tomcat01 tomcat02,用来区分容器 -d 后台方式运行 -it 使用交互式方式运行，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:容器端口（常用） -p 容器端口 容器端口 -p 随机指定端口 # 测试 启动并进入容器 [root@iZuf60urtgz7708wda7blnZ ~]# docker run -it centos /bin/bash [root@87b2db262965 /]# [root@87b2db262965 /]# ls # 查看容器内的centos，基础版本，很多命令都是不完善的！ bin dev etc home lib lib64 lost+found media mnt opt proc root run sbin srv sys tmp usr var # 从容器中退回主机 [root@87b2db262965 /]# ls bin dev etc home lib lib64 lost+found media mnt opt proc root run sbin srv sys tmp usr var
列出所有的运行的容器
# docker ps 命令 # 列出当前正在运行的容器 -a # 列出当前正在运行的容器 + 历史运行过的容器 -n=？ # 显示最近创建的容器 -q # 只显示容器的编号 [root@iZuf60urtgz7708wda7blnZ /]# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES [root@iZuf60urtgz7708wda7blnZ /]# docker ps -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 87b2db262965 centos "/bin/bash" 4 minutes ago Exited (0) 2 minutes ago trusting_hodgkin 80c26b193d2b feb5d9fea6a5 "/hello" 2 hours ago Exited (0) 2 hours ago gracious_grothendieck [root@iZuf60urtgz7708wda7blnZ /]#
退出容器
exit # 直接容器停止并退出 Ctrl + P + Q # 容器不停止退出
删除容器
docker rm 容器id # 删除指定的容器，不能删除正在运行的容器 强行删除-f docker rm -f $(docker ps -aq) # 删除所有的容器 docker ps -a -q|xargs docker rm # 删除所有的容器
启动和停止容器的操作
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
常用其他命令
后台启动容器
# 命令 docker run -d 镜像名！ [root@iZuf60urtgz7708wda7blnZ /]# docker run -d centos # 问题docker ps，发现centos停了 # 常见的坑：docker容器使用后台运行，就必须有一个前台进程，docker发现没有应用，就会自动停止 # nginx，容器启动后，发现自己没有提供服务，就会立刻停止，就是没有程序了
查看日志
docker logs -f -t --tail 容器，没有日志 # 自己编写一段shell脚本 [root@iZuf60urtgz7708wda7blnZ /]# docker run -d centos /bin/sh -c "while true;do echo chaoge;sleep 1;done" # [root@iZuf60urtgz7708wda7blnZ /]# docker ps CONTAINER ID IMAGE 2d11711ad39a centos # 显示日志 -tf --tail number # 要显示的日志条数 [root@iZuf60urtgz7708wda7blnZ /]# docker logs -f -t --tail 10 2d11711ad39a
查看容器中进程信息
# 命令 docker top 容器id UID PID PPID C STIME TTY root 3189 3168 0 16:22 ? root 3238 3189 0 16:22 ?
查看镜像的元数据
# 命令
docker inspect 2d11711ad39a
# 测试
[root@iZuf60urtgz7708wda7blnZ ~]# docker inspect 2d11711ad39a
[
{
"Id": "2d11711ad39a7e042d0e4ff2ff458bcd920aab6f6e149f4c923ea148cf799025",
"Created": "2022-04-04T08:16:27.866845228Z",
"Path": "/bin/sh",
"Args": [
"-c",
"while true;do echo chaoge;sleep 1;done"
],
"State": {
"Status": "exited",
"Running": false,
"Paused": false,
"Restarting": false,
"OOMKilled": false,
"Dead": false,
"Pid": 0,
"ExitCode": 137,
"Error": "",
"StartedAt": "2022-04-04T08:22:41.554391049Z",
"FinishedAt": "2022-04-04T08:25:17.909006976Z"
},
"Image": "sha256:5d0da3dc976460b72c77d94c8a1ad043720b0416bfc16c52c45d4847e53fadb6",
"ResolvConfPath": "/var/lib/docker/containers/2d11711ad39a7e042d0e4ff2ff458bcd920aab6f6e149f4c923ea148cf799025/resolv.conf",
"HostnamePath": "/var/lib/docker/containers/2d11711ad39a7e042d0e4ff2ff458bcd920aab6f6e149f4c923ea148cf799025/hostname",
"HostsPath": "/var/lib/docker/containers/2d11711ad39a7e042d0e4ff2ff458bcd920aab6f6e149f4c923ea148cf799025/hosts",
"LogPath": "/var/lib/docker/containers/2d11711ad39a7e042d0e4ff2ff458bcd920aab6f6e149f4c923ea148cf799025/2d11711ad39a7e042d0e4ff2ff458bcd920aab6f6e149f4c923ea148cf799025-json.log",
"Name": "/magical_burnell",
"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,
"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",
"ConsoleSize": [
0,
0
],
"Isolation": "",
"CpuShares": 0,
"Memory": 0,
"NanoCpus": 0,
"CgroupParent": "",
"BlkioWeight": 0,
"BlkioWeightDevice": [],
"BlkioDeviceReadBps": null,
"BlkioDeviceWriteBps": null,
"BlkioDeviceReadIOps": null,
"BlkioDeviceWriteIOps": null,
"CpuPeriod": 0,
"CpuQuota": 0,
"CpuRealtimePeriod": 0,
"CpuRealtimeRuntime": 0,
"CpusetCpus": "",
"CpusetMems": "",
"Devices": [],
"DeviceCgroupRules": null,
"DeviceRequests": null,
"KernelMemory": 0,
"KernelMemoryTCP": 0,
"MemoryReservation": 0,
"MemorySwap": 0,
"MemorySwappiness": null,
"OomKillDisable": false,
"PidsLimit": null,
"Ulimits": null,
"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"
],
"ReadonlyPaths": [
"/proc/bus",
"/proc/fs",
"/proc/irq",
"/proc/sys",
"/proc/sysrq-trigger"
]
},
"GraphDriver": {
"Data": {
"LowerDir": "/var/lib/docker/overlay2/b3399c88a93d92b98c01f1acfe7b393a37d56956fdfb9f41386bfb9bb8dbf711-init/diff:/var/lib/docker/overlay2/6a9c5fbcc5414ac4002ed644ed01881364a407871b38e5d8e0d1a134db63637f/diff",
"MergedDir": "/var/lib/docker/overlay2/b3399c88a93d92b98c01f1acfe7b393a37d56956fdfb9f41386bfb9bb8dbf711/merged",
"UpperDir": "/var/lib/docker/overlay2/b3399c88a93d92b98c01f1acfe7b393a37d56956fdfb9f41386bfb9bb8dbf711/diff",
"WorkDir": "/var/lib/docker/overlay2/b3399c88a93d92b98c01f1acfe7b393a37d56956fdfb9f41386bfb9bb8dbf711/work"
},
"Name": "overlay2"
},
"Mounts": [],
"Config": {
"Hostname": "2d11711ad39a",
"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",
"while true;do echo chaoge;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": "94a43185af62d515a0f391954977d3996c700bfc04df6821a1ae65827672d877",
"HairpinMode": false,
"LinkLocalIPv6Address": "",
"LinkLocalIPv6PrefixLen": 0,
"Ports": {},
"SandboxKey": "/var/run/docker/netns/94a43185af62",
"SecondaryIPAddresses": null,
"SecondaryIPv6Addresses": null,
"EndpointID": "",
"Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"IPAddress": "",
"IPPrefixLen": 0,
"IPv6Gateway": "",
"MacAddress": "",
"Networks": {
"bridge": {
"IPAMConfig": null,
"Links": null,
"Aliases": null,
"NetworkID": "2118b149ede8f181719cc4827755cbb9bbc0caebe7168670e913c067f9a6de55",
"EndpointID": "",
"Gateway": "",
"IPAddress": "",
"IPPrefixLen": 0,
"IPv6Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"MacAddress": "",
"DriverOpts": null
}
}
}
}
]
进入当前正在运行的容器
# 我们通常容器都是使用后台方式运行的，需要进入容器，修改一些配置 # 命令 docker exec -it 容器id bashShell # 测试 [root@iZuf60urtgz7708wda7blnZ ~]# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES cfc34d94ad07 centos "/bin/bash" 22 minutes ago Up 22 minutes inspiring_cerf [root@iZuf60urtgz7708wda7blnZ ~]# docker exec -it cfc34d94ad07 /bin/bash [root@cfc34d94ad07 /]# ls bin dev etc home lib lib64 lost+found media mnt opt proc root run sbin srv sys tmp usr var [root@cfc34d94ad07 /]# ps -ef UID PID PPID C STIME TTY TIME CMD root 1 0 0 08:09 pts/0 00:00:00 /bin/bash root 16 0 0 08:32 pts/1 00:00:00 /bin/bash root 32 16 0 08:32 pts/1 00:00:00 ps -ef # 方式二 docker attach 容器id # 测试 [root@iZuf60urtgz7708wda7blnZ ~]# docker attach cfc34d94ad07 正在执行的代码...... # docker exec # 进入容器后开启一个新的终端，可以在里面操作（常用） # docker attach # 进入容器正在执行的终端，不会启动新的进程！
从容器内拷贝文件到主机上
# 查看当前主机目录下 [root@iZuf60urtgz7708wda7blnZ chaoge]# ls chaoge.java [root@iZuf60urtgz7708wda7blnZ chaoge]# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 2b484eee3d9b centos "/bin/bash" About a minute ago Up About a minute suspicious_kirch # 进入docker容器内部 [root@iZuf60urtgz7708wda7blnZ chaoge]# docker attach 2b484eee3d9b [root@2b484eee3d9b /]# cd /home [root@2b484eee3d9b /]# ls bin dev etc home lib lib64 lost+found media mnt opt proc root run sbin srv sys tmp usr var # 在容器内新建一个文件 [root@2b484eee3d9b /]# touch test.java [root@2b484eee3d9b /]# ls bin dev etc home lib lib64 lost+found media mnt opt proc root run sbin srv sys test.java tmp usr var [root@2b484eee3d9b /]# exit exit [root@iZuf60urtgz7708wda7blnZ chaoge]# docker ps -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 2b484eee3d9b centos "/bin/bash" 2 minutes ago Exited (0) 6 seconds ago suspicious_kirch # 将这个文件拷贝出来到主机上 [root@iZuf60urtgz7708wda7blnZ chaoge]# docker cp 2b484eee3d9b:/home/test.java /home # 拷贝是一个手动过程，未来我们使用 -v卷的技术 可以实现，自动同步 /home /home
小结
