mysql - How to "undeclare" volumes in docker image?

Question

I am writing a Dockerfile for setting up an image for testing a web application. I am basing it on the tutum/lamp image (https://github.com/tutumcloud/tutum-docker-lamp/blob/master/Dockerfile) because that seems to be a good base to start from.

As part of my dockerfile, I want to create a mysql database and set up some stuff in it. However, the tutum/lamp image declares VOLUME ["/etc/mysql", "/var/lib/mysql" ], so if I understand correctly, any changes that I make to the MySQL database in the Dockerfile will not be persisted.

• Do I understand that correctly?

If yes,

• Is there a way to "undeclare" those volumes so that those directories will be part of the union file system like everything else?

Thanks!

Answer 1

You can't really undeclare a volume, but you can build your own version of the original image by modifying its dockerfile.