Docker容器数据卷
容器数据卷
概念
docker的理念
将应用和环境打包成一个镜像！
如果数据都在容器中， 那么我们容器删除， 数据就会丢失！需求：数据可以持久化
容器之间可以有一个数据共享的技术！Docker容器中产生的数据， 同步到本地！这就是卷技术！目录的挂载，将我们容器内的目录， 挂载到Linux上面！
总结：容器的持久化和同步操作！容器间也是可以数据共享的！
使用数据卷
方式一：直接使用命令来挂载， -v
docker run -it -v 主机目录：容器目录
# 测试
docker run -it -v /home/ceshi:/home centos /bin/bash
# 启动后我们可以通过docker inspect 容器id 查看容器的详细信息
docker inspect 605792482b78
[
{
"Id": "605792482b78ec465aeb1bc3435072c1d15ef5bb6c121b5435a2d54ccb6abd0f",
"Created": "2021-07-07T04:05:06.1318939Z",
"Path": "/bin/bash",
"Args": [],
"State": {
"Status": "running",
"Running": true,
"Paused": false,
"Restarting": false,
"OOMKilled": false,
"Dead": false,
"Pid": 4399,
"ExitCode": 0,
"Error": "",
"StartedAt": "2021-07-07T04:05:06.5403594Z",
"FinishedAt": "0001-01-01T00:00:00Z"
},
"Image": "sha256:300e315adb2f96afe5f0b2780b87f28ae95231fe3bdd1e16b9ba606307728f55",
"ResolvConfPath": "/var/lib/docker/containers/605792482b78ec465aeb1bc3435072c1d15ef5bb6c121b5435a2d54ccb6abd0f/resolv.conf",
"HostnamePath": "/var/lib/docker/containers/605792482b78ec465aeb1bc3435072c1d15ef5bb6c121b5435a2d54ccb6abd0f/hostname",
"HostsPath": "/var/lib/docker/containers/605792482b78ec465aeb1bc3435072c1d15ef5bb6c121b5435a2d54ccb6abd0f/hosts",
"LogPath": "/var/lib/docker/containers/605792482b78ec465aeb1bc3435072c1d15ef5bb6c121b5435a2d54ccb6abd0f/605792482b78ec465aeb1bc3435072c1d15ef5bb6c121b5435a2d54ccb6abd0f-json.log",
"Name": "/elastic_sinoussi",
"RestartCount": 0,
"Driver": "overlay2",
"Platform": "linux",
"MountLabel": "",
"ProcessLabel": "",
"AppArmorProfile": "",
"ExecIDs": null,
"HostConfig": {
"Binds": [
"/Users/dm/ceshi:/home"
],
"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/overlay2/4bd0730f1688f7084071236f77ed381561be8a1fd0ae3aa335fe3f4fb97401f6-init/diff:/var/lib/docker/overlay2/44e554333aeb2e37bb18ba3ae2e6e8ee83f4e6eeade745b7ac39ded0c88b3f3f/diff",
"MergedDir": "/var/lib/docker/overlay2/4bd0730f1688f7084071236f77ed381561be8a1fd0ae3aa335fe3f4fb97401f6/merged",
"UpperDir": "/var/lib/docker/overlay2/4bd0730f1688f7084071236f77ed381561be8a1fd0ae3aa335fe3f4fb97401f6/diff",
"WorkDir": "/var/lib/docker/overlay2/4bd0730f1688f7084071236f77ed381561be8a1fd0ae3aa335fe3f4fb97401f6/work"
},
"Name": "overlay2"
},
"Mounts": [
{
"Type": "bind",
"Source": "/Users/dm/ceshi",
"Destination": "/home",
"Mode": "",
"RW": true,
"Propagation": "rprivate"
}
],
"Config": {
"Hostname": "605792482b78",
"Domainname": "",
"User": "",
"AttachStdin": true,
"AttachStdout": true,
"AttachStderr": true,
"Tty": true,
"OpenStdin": true,
"StdinOnce": true,
"Env": [
"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
],
"Cmd": [
"/bin/bash"
],
"Image": "centos",
"Volumes": null,
"WorkingDir": "",
"Entrypoint": null,
"OnBuild": null,
"Labels": {
"org.label-schema.build-date": "20201204",
"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": "fe488aec7aaa3a6bf80de5c7b26f5b88ac3f2bc0daf99a88d16d98958aa6256f",
"HairpinMode": false,
"LinkLocalIPv6Address": "",
"LinkLocalIPv6PrefixLen": 0,
"Ports": {},
"SandboxKey": "/var/run/docker/netns/fe488aec7aaa",
"SecondaryIPAddresses": null,
"SecondaryIPv6Addresses": null,
"EndpointID": "5681466c86468c0787979446e3e62ab7b914841208325b3b93bead8e02919cc1",
"Gateway": "172.17.0.1",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"IPAddress": "172.17.0.5",
"IPPrefixLen": 16,
"IPv6Gateway": "",
"MacAddress": "02:42:ac:11:00:05",
"Networks": {
"bridge": {
"IPAMConfig": null,
"Links": null,
"Aliases": null,
"NetworkID": "231fbbf145a9be8f27f4d0de98f3950dc170218f64b3a24ab416b43a491a27cd",
"EndpointID": "5681466c86468c0787979446e3e62ab7b914841208325b3b93bead8e02919cc1",
"Gateway": "172.17.0.1",
"IPAddress": "172.17.0.5",
"IPPrefixLen": 16,
"IPv6Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"MacAddress": "02:42:ac:11:00:05",
"DriverOpts": null
}
}
}
}
]
# 可以同时在容器内和宿主机修改数据同步映射
数据卷的好处
修改只需要在本地修改即可， 容器内会自动同步！
Dockerfile
Dockerfile是用来构建docker镜像的构建文件，命令文件， 通过这个脚本可以生成镜像，镜像是一层的， 脚步是一个一个的命令， 每个命令都是一层
方式二、Dockerfile构建
# 在一个目录下创建一个dockerfile文件，名字可以随意，建议Dockerfile。编写如下命令
FROM centos
VOLUME ["volume01", "volume02"]
CMD echo "----end----"
CMD /bin/bash
# 运行dockerfile文件(mac)
docker build -f dockerfile1 -t test/centos .
[+] Building 0.1s (5/5) FINISHED
=> [internal] load build definition from dockerfile1 0.0s
=> => transferring dockerfile: 124B 0.0s
=> [internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [internal] load metadata for docker.io/library/centos:latest 0.0s
=> [1/1] FROM docker.io/library/centos 0.0s
=> exporting to image 0.0s
=> => exporting layers 0.0s
=> => writing image sha256:02c2769725446694db5e95968ba34f1ce7e2ef38daa6f 0.0s
=> => naming to docker.io/test/centos
# 查看打包的镜像
docker images
# 运行镜像
dockder run -it 镜像id
# 测试查看容器卷挂载
docker ps # 查看运行中的镜像
docker inspect 容器id # 查看容器挂载
"Mounts": [
{
"Type": "volume",
"Name": "8b647cb0e98a96de1cc4d726e81df009962269239599eb8bc250885c39412777",
"Source": "/var/lib/docker/volumes/8b647cb0e98a96de1cc4d726e81df009962269239599eb8bc250885c39412777/_data",
"Destination": "/home/volume01",
"Driver": "local",
"Mode": "",
"RW": true,
"Propagation": ""
},
{
"Type": "volume",
"Name": "f70ee35a1feafccd88b4957843d04248086174751ff5db8d30fe0d026f95c641",
"Source": "/var/lib/docker/volumes/f70ee35a1feafccd88b4957843d04248086174751ff5db8d30fe0d026f95c641/_data",
"Destination": "/home/volume02",
"Driver": "local",
"Mode": "",
"RW": true,
"Propagation": ""
}
]
实现多个mysql数据共享
docker run -d -p 3306:3306 -v /etc/mysql/conf.d -v /var/lib/mysql -e MYSQL_ROOT_PASSWORD=123456 -name mysql01 mysql:5.7
docker run -d -p 3306:3306 -e MYSQL_ROOT_PASSWORD=123456 -name mysql02 --volumes-from mysql01 mysql:5.7
# 此时可以实现两个容器数据同步
结论
容器之间配置信息的传递， 数据卷容器的生命周期一直持续到没有容器使用为止。但是一旦你持久化道本地，这个时候，本地的数据是不会删除的！
