⑨. VOLUME 创建数据卷挂载点
①. 把容器的某些文件夹映射到主机外部
②. 写法:这个一般写在最后
VOLUME ["/var/log/"] #可以是JSON数组
VOLUME /var/log #可以直接写
VOLUME /var/log /var/db #可以空格分割多个
③. 注意:用VOLUME声明了卷,那么以后对于卷内容的修改会被丢弃,所以一定在volume声明之前修改内容
FROM alpine RUN mkdir /hello && mkdir /app RUN echo 1111 > /hello/a.txt RUN echo 2222 > /app/b.txt # 挂在容器内的指定文件夹,如果不存在则创建 # 指定了volume,即使启动容器没有指定-v参数,我们也会自动进行匿名卷挂载 # 这里的 hello app 都是容器里面的文件夹,请你在使用镜像启动容器的时候,自动给宿主机上挂载 VOLUME [ "/hello","/app"] # 用VOLUME声明了卷,那么以后对于卷内容的修改会被丢弃,所以一定在volume声明之前修改内容 RUN echo 6666 > /hello/a.txt RUN echo 8888 > /app/b.txt CMD ping baidu.com
[root@i-id8g0yu9 ~]# docker build --no-cache -t dockerfileworkvolume:v1 -f dockerfileVOLUME . Sending build context to Docker daemon 2.474MB Step 1/8 : FROM alpine ---> 6dbb9cc54074 Step 2/8 : RUN mkdir /hello && mkdir /app ---> Running in 36ed19f5446d Removing intermediate container 36ed19f5446d ---> 42af237e9a7e Step 3/8 : RUN echo 1111 > /hello/a.txt ---> Running in 662511d7ddb7 Removing intermediate container 662511d7ddb7 ---> f744129965ae Step 4/8 : RUN echo 2222 > /app/b.txt ---> Running in a8321f4f8d98 Removing intermediate container a8321f4f8d98 ---> 1d03ca553eb7 Step 5/8 : VOLUME [ "/hello","/app"] ---> Running in 1d4ec1c1e8f7 Removing intermediate container 1d4ec1c1e8f7 ---> 4e76b09577d3 Step 6/8 : RUN echo 6666 > /hello/a.txt ---> Running in 912d739bb4d4 Removing intermediate container 912d739bb4d4 ---> da35323435dd Step 7/8 : RUN echo 8888 > /app/b.txt ---> Running in bab5aceb4f7a Removing intermediate container bab5aceb4f7a ---> 73c45738db48 Step 8/8 : CMD ping baidu.com ---> Running in 05bedb917269 Removing intermediate container 05bedb917269 ---> a01440e2a675 Successfully built a01440e2a675 Successfully tagged dockerfileworkvolume:v1 [root@i-id8g0yu9 ~]# docker run -d dockerfileworkvolume:v1 56ef53c95a6c7f96a8cf308be8393ee53fb70a4802f7c43e4519cf5fab438abc [root@i-id8g0yu9 ~]# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 56ef53c95a6c dockerfileworkvolume:v1 "/bin/sh -c 'ping ba…" 4 seconds ago Up 3 seconds stupefied_ptolemy b4d8744b6a92 dockerfileworkdir:v1 "/bin/sh -c 'ping ba…" 49 minutes ago Up 49 minutes myworkdir [root@i-id8g0yu9 ~]# docker inspect 56ef53c95a6c [ { "Id": "56ef53c95a6c7f96a8cf308be8393ee53fb70a4802f7c43e4519cf5fab438abc", "Created": "2021-04-18T14:45:15.782034507Z", "Path": "/bin/sh", "Args": [ "-c", "ping baidu.com" ], "State": { "Status": "running", "Running": true, "Paused": false, "Restarting": false, "OOMKilled": false, "Dead": false, "Pid": 8131, "ExitCode": 0, "Error": "", "StartedAt": "2021-04-18T14:45:16.143344962Z", "FinishedAt": "0001-01-01T00:00:00Z" }, "Image": "sha256:a01440e2a675dab49c9fb9c788e890c81913e7f15de3a4071fec51a5a5475aea", "ResolvConfPath": "/var/lib/docker/containers/56ef53c95a6c7f96a8cf308be8393ee53fb70a4802f7c43e4519cf5fab438abc/resolv.conf", "HostnamePath": "/var/lib/docker/containers/56ef53c95a6c7f96a8cf308be8393ee53fb70a4802f7c43e4519cf5fab438abc/hostname", "HostsPath": "/var/lib/docker/containers/56ef53c95a6c7f96a8cf308be8393ee53fb70a4802f7c43e4519cf5fab438abc/hosts", "LogPath": "/var/lib/docker/containers/56ef53c95a6c7f96a8cf308be8393ee53fb70a4802f7c43e4519cf5fab438abc/56ef53c95a6c7f96a8cf308be8393ee53fb70a4802f7c43e4519cf5fab438abc-json.log", "Name": "/stupefied_ptolemy", "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/bca4693743c24765c88e89c05892e9b8f3f0b39918c5a400d58c9b9db5ec450c-init/diff:/var/lib/docker/overlay2/8623d3705ceea6e0f9349ac0645977e1fa8c45cc9ea6337115098c03d259a200/diff:/var/lib/docker/overlay2/960ab6c1f64fd999f44c90be57256371c1e5dd43f115e1d2ff11037408a8ffc8/diff:/var/lib/docker/overlay2/871b7ffab75435d24006f3f7bff690c903328b273764a7e4ab1922bece5b8ad7/diff:/var/lib/docker/overlay2/43d78cac3804ed1dc62283f315a185e8136796e5779d9ee8717fa9a2d99d6edd/diff", "MergedDir": "/var/lib/docker/overlay2/bca4693743c24765c88e89c05892e9b8f3f0b39918c5a400d58c9b9db5ec450c/merged", "UpperDir": "/var/lib/docker/overlay2/bca4693743c24765c88e89c05892e9b8f3f0b39918c5a400d58c9b9db5ec450c/diff", "WorkDir": "/var/lib/docker/overlay2/bca4693743c24765c88e89c05892e9b8f3f0b39918c5a400d58c9b9db5ec450c/work" }, "Name": "overlay2" }, "Mounts": [ { "Type": "volume", "Name": "65adbd1e4997c8df05a05b30ab1a2c3df970e19b0dd38f579f428ec8442810b9", "Source": "/var/lib/docker/volumes/65adbd1e4997c8df05a05b30ab1a2c3df970e19b0dd38f579f428ec8442810b9/_data", "Destination": "/app", "Driver": "local", "Mode": "", "RW": true, "Propagation": "" }, { "Type": "volume", "Name": "1c3739d31bd487d847d0101ac2d48bbdb661cc9cbe97799de86181c2f50d98db", "Source": "/var/lib/docker/volumes/1c3739d31bd487d847d0101ac2d48bbdb661cc9cbe97799de86181c2f50d98db/_data", "Destination": "/hello", "Driver": "local", "Mode": "", "RW": true, "Propagation": "" } ], "Config": { "Hostname": "56ef53c95a6c", "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", "ping baidu.com" ], "Image": "dockerfileworkvolume:v1", "Volumes": { "/app": {}, "/hello": {} }, "WorkingDir": "", "Entrypoint": null, "OnBuild": null, "Labels": {} }, "NetworkSettings": { "Bridge": "", "SandboxID": "d4490ef3887d03e22812b820c963c82a8edfe45c5f3141676a03df8d7aecfc51", "HairpinMode": false, "LinkLocalIPv6Address": "", "LinkLocalIPv6PrefixLen": 0, "Ports": {}, "SandboxKey": "/var/run/docker/netns/d4490ef3887d", "SecondaryIPAddresses": null, "SecondaryIPv6Addresses": null, "EndpointID": "671b069ea364448c75dbbb4d9365c60b46abf392bdcca26bc9713cf9051baa2e", "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, "NetworkID": "24c026c0a26cfb78a82f033887c3669c4ccaf63060e02fefe51e958cb5037c32", "EndpointID": "671b069ea364448c75dbbb4d9365c60b46abf392bdcca26bc9713cf9051baa2e", "Gateway": "172.17.0.1", "IPAddress": "172.17.0.3", "IPPrefixLen": 16, "IPv6Gateway": "", "GlobalIPv6Address": "", "GlobalIPv6PrefixLen": 0, "MacAddress": "02:42:ac:11:00:03", "DriverOpts": null } } } } ] [root@i-id8g0yu9 ~]# cd /var/lib/docker/volumes/65adbd1e4997c8df05a05b30ab1a2c3df970e19b0dd38f579f428ec8442810b9/_data [root@i-id8g0yu9 _data]# ls b.txt [root@i-id8g0yu9 _data]# cat b.txt # 注意这里还有追加6666或者8888 2222 [root@i-id8g0yu9 _data]#
