MySQL databases are gone when the docker container

问题:

I am new to docker world. I want to install some of the software packages into docker image. So I have taken Ubuntu:14.04 docker image and installed MySQL server there. Then did some works with it. Once I exit from docker image and commit it. But once I start docker container, databases which was created were gone. What would be the reason for this?

回答1:

If you start your mysql database with docker run ..., it creates each time a new and fresh container with it. You can find your old one in the list of containers with docker ps -a and you have to start your old container (docker start <container>) if you want the last state. Otherwise you have a fresh database derived from your image.