应用场景：mysql容器在被销毁之后，数据能够长久化

初始化一个mysql容器

# 为了便于测试，设置root明码为空docker run -d --name mysql1 -e MYSQL_ALLOW_EMPTY_PASSWORD=yes mysql:latest

查看mysql容器对应的volume

Mountpoint 的值 /var/lib/docker/volumes/5bcd1cb1088a71fbf595fb817ea9511501f794ac17971529cd3451102f872a87/_data，就是mysql容器保留数据到虚拟机的中央了

[vagrant@docker-node1 ~]$ docker volume lsDRIVER VOLUME NAMElocal 5bcd1cb1088a71fbf595fb817ea9511501f794ac17971529cd3451102f872a87[vagrant@docker-node1 ~]$ docker volume inspect 5bcd1cb1088a71fbf595fb817ea9511501f794ac17971529cd3451102f872a87[    {        "CreatedAt": "2018-07-03T12:12:36Z",        "Driver": "local",        "Labels": null,        "Mountpoint": "/var/lib/docker/volumes/5bcd1cb1088a71fbf595fb817ea9511501f794ac17971529cd3451102f872a87/_data",        "Name": "5bcd1cb1088a71fbf595fb817ea9511501f794ac17971529cd3451102f872a87",        "Options": null,        "Scope": "local"    }]

删除mysql容器

docker container stop mysql1docker container rm mysql1

删除之后发现该容器对应的volume还是存在的，这也就是mysql数据的长久化了

如果是降级mysql的版本，因为volume data的存在，可能低版本的mysql不兼容，导致呈现问题，此时还须要删除volume data。

命名Volume

[vagrant@docker-node1 ~]$ docker run -d -v mysql:/var/lib/mysql --name mysql2 -e MYSQL_ALLOW_EMPTY_PASSWORD=yes mysql:latest028c9a31c4b1bbe0ef1aa40517e881fb655d2efb81d5591460c323b320ac2e84[vagrant@docker-node1 ~]$ docker volume lsDRIVER VOLUME NAMElocal mysql[vagrant@docker-node1 ~]$ docker volume inspect mysql[    {        "CreatedAt": "2018-07-03T12:25:48Z",        "Driver": "local",        "Labels": null,        "Mountpoint": "/var/lib/docker/volumes/mysql/_data",        "Name": "mysql",        "Options": null,        "Scope": "local"    }]

长久化数据的应用

进入到mysql2容器，创立一个数据库，名称为docker

docker exec -it mysql2 /bin/shmysql -u rootmysql> create database docker;mysql> show databases;+--------------------+| Database |+--------------------+| docker || information_schema || mysql || performance_schema || sys |+--------------------+5 rows in set (0.00 sec)

而后删除mysql2容器

docker container stop mysql2docker container rm mysql2

创立一个mysql3容器

docker run -d -v mysql:/var/lib/mysql --name mysql3 -e MYSQL_ALLOW_EMPTY_PASSWORD=yes mysql:latestdocker exec -it mysql3 /bin/shmysql -u rootmysql> show databases;+--------------------+| Database |+--------------------+| docker || information_schema || mysql || performance_schema || sys |+--------------------+5 rows in set (0.00 sec)

nice！发现docker数据库在容器mysql3中仍然是能够应用的。