[系统运维]Docker数据卷

Docker数据卷

数据卷挂载

命令方式挂载

命令挂载说明 -v [宿主机目录|挂载别名:]容器内目录[:ro|rw]

1. 匿名挂载

   # 匿名挂载
   docker run -it -v /root/volume1 --name centos1 centos /bin/bash
   
   # -d 后台运行
   # -v 数据卷挂载  容器内目录
   # --name 命名容器
   

   查看元数据信息

   # 查看元数据
   docker inspect centos1
   
   # 挂载信息如下
   "Mounts": [
   	{
           "Type": "volume",
           "Name": "9c795e1c6bc195860d2b93fdc9f1cc504f2ffaf7b8a46d0762d0584b123fe72d",
           "Source": "/var/lib/docker/volumes/9c795e1c6bc195860d2b93fdc9f1cc504f2ffaf7b8a46d0762d0584b123fe72d/_data",
           "Destination": "/root/volume1",
           "Driver": "local",
           "Mode": "",
           "RW": true,
           "Propagation": ""
   	}
   ],
   
   
   # Type  		挂载类型
   # Name  		匿名挂载的随机名称
   # Source 		宿主机挂载目的地址
   # Destination 	容器内挂载的目录
   # RW			是否可读可写
   

2. 具名挂载

   # 具名挂载
   docker run -it --name centos1 -v volume1:/root/volume1 centos /bin/bash
   # -v 数据卷挂载  映射名称:容器内目录
   
   # 挂载信息如下
   "Mounts": [
       {
           "Type": "volume",
           "Name": "volume1",
           "Source": "/var/lib/docker/volumes/volume1/_data",
           "Destination": "/root/volume1",
           "Driver": "local",
           "Mode": "z",
           "RW": true,
           "Propagation": ""
       }
   ],
   
   # 具名挂载指定权限
   docker run -it --name centos1 -v volume2:/root/volume2:ro centos /bin/bash
   # -v 数据卷挂载  映射名称:容器内目录:权限
   # 		ro 权限：只读权限，容器内挂载目录无法创建文件或目录
   
   # 挂载信息如下
   "Mounts": [
       {
           "Type": "volume",
           "Name": "volume2",
           "Source": "/var/lib/docker/volumes/volume2/_data",
           "Destination": "/root/volume2",
           "Driver": "local",
           "Mode": "ro",
           "RW": false,
           "Propagation": ""
       }
   ],
   
   

3. 绑定挂载

   通具名挂载类似，仅是名称更改为宿主机目录

   # 具名挂载
   docker run -it --name centos1 -v /data/volume1:/root/volume1 centos /bin/bash
   # -v 数据卷挂载  宿主机目录:容器内目录
   
   # 挂载信息如下
   "Mounts": [
       {
           "Type": "bind",
           "Source": "/data/volume1",
           "Destination": "/root/volume1",
           "Mode": "",
           "RW": true,
           "Propagation": "rprivate"
       }
   ],
   
   # 具名挂载指定权限
   docker run -it --name centos1 -v /data/volume2:/root/volume2:ro centos /bin/bash
   # -v 数据卷挂载  宿主机目录:容器内目录:权限
   # 		ro 权限：只读权限，容器内挂载目录无法创建文件或目录
   
   # 挂载信息如下
   "Mounts": [
       {
           "Type": "bind",
           "Source": "/data/volume2",
           "Destination": "/root/volume2",
           "Mode": "ro",
           "RW": false,
           "Propagation": "rprivate"
       }
   ],
   

? 所有挂载的数据在宿主机和容器内都可以找到，并且容器删除后宿主机内的映射的数据卷信息不会被删除

Dockerfile挂载

1. 创建Dockerfile文件

2. 编写Dockerfile文件

   # 基于 centos镜像
   FROM centos
   
   # 挂载数据卷列表(匿名挂载)
   VOLUME ["/root/volume1", "volume2"]
   
   # 输出命令
   CMD echo "-- Dockerfile end --"
   
   # 命令
   CMD /bin/bash
   
   

3. 使用Dockerfile构建镜像

   # 后面的 . 一定要有
   docker build -f Dockerfile -t mycentos .
   # -f 指定Dockerfile文件
   # -t 指定生成的镜像名称    名称[:版本tag]
   
   # 构建成功示例
   [root@localhost ~]# docker build -f Dockerfile -t mycentos .
   Sending build context to Docker daemon  23.55kB
   Step 1/4 : FROM centos
    ---> 5d0da3dc9764
   Step 2/4 : VOLUME ["/root/volume1", "volume2"]
    ---> Running in 5a2fe4403328
   Removing intermediate container 5a2fe4403328
    ---> 8b9b9c7683d8
   Step 3/4 : CMD echo "-- Dockerfile end --"
    ---> Running in 5ee26484266a
   Removing intermediate container 5ee26484266a
    ---> 811bfb554204
   Step 4/4 : CMD /bin/bash
    ---> Running in 8c143cabb6ab
   Removing intermediate container 8c143cabb6ab
    ---> fe7a7c3725ce
   Successfully built fe7a7c3725ce
   Successfully tagged mycentos:latest
   
   

4. 启动容器

   # 启动容器
   docker run -it --name mycentos1 mycentos /bin/bash
   
   # 数据卷挂载信息
   "Mounts": [
       {
           "Type": "volume",
           "Name": "4d8b613894f543242d42013074ccca6079e4213caca015ec51adf281c611de07",
           "Source": "/var/lib/docker/volumes/4d8b613894f543242d42013074ccca6079e4213caca015ec51adf281c611de07/_data",
           "Destination": "/root/volume1",
           "Driver": "local",
           "Mode": "",
           "RW": true,
           "Propagation": ""
       },
       {
           "Type": "volume",
           "Name": "66d49c90c42bd312346559f1747d6fea317133155501da9c257cd9cf6b689083",
           "Source": "/var/lib/docker/volumes/66d49c90c42bd312346559f1747d6fea317133155501da9c257cd9cf6b689083/_data",
           "Destination": "volume2",
           "Driver": "local",
           "Mode": "",
           "RW": true,
           "Propagation": ""
       }
   ],
   

数据卷容器共享

通过挂载共享数据卷，实现多个容器数据共享

# 启动第一个容器
docker run -it --name centos1 -v /data/volume1:/root/volume1 centos /bin/bash

# 启动第二个容器
docker run -it --name centos2 --volumes-from centos1 centos /bin/bash

# --volumes-from  从其他容器挂载

运行结果

在此，实现多个容器数据卷共享。

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