MySQL container: grant access and create a new image - mysql

Question

I'm trying to use MySQL docker container in my host system to make installation and configuration processes much easier and faster.
So, I've pulled an image from:
https://hub.docker.com/r/mysql/mysql-server/
Then started container based on this image..
Container started fine, but I was not able to connect to this DB from my host system (everything is ok if I try to connect from container). It failed with a message:
ERROR 1130 (HY000): Host '<here goes my IP>' is not allowed to connect to this MySQL server
So, as I understand, my root user has no enough permissions.
I've entered my container:
docker exec -it mysql bash
Connected to DB:
mysql -uroot -ppassword
Updated permissions for my root user:
use mysql;
UPDATE user SET Host="%" WHERE User='root';
It's updated fine.
Than I decided to save my updated image somehow... I've found this guide:
http://docs.oracle.com/cd/E52668_01/E75728/html/section_c5q_n2z_fp.html
After executing:
docker stop mysql
docker commit -m "Fixed permissions for root user" -a "Few words about author" `docker ps -l -q` myrepo/mysql:v1
docker rm mysql
docker run --name new-mysql -p 3306:3306 -e MYSQL_ROOT_PASSWORD=pass -d myrepo/mysql:v1
I've found that my root user hasn't permissions again.
What is wrong here?
How to public my updated image into my Dockerhub?

Answer 1

My original answer is for persisting the change in the MySQL data after it has been initialized. But since you want to do this in the image for every initialization automatically there is a different approach for this. You can use one of the following options:
There is an environment variable called MYSQL_ROOT_HOST for this image where you can set the host (https://github.com/mysql/mysql-docker/blob/mysql-server/5.7/docker-entrypoint.sh#L63-L69). You should be able to set this to % to allow all hosts to connect as root such as -e MYSQL_ROOT_HOST="%".
The image supports adding SQL files to /docker-entrypoint-initdb.d/ to be initialized on startup (https://github.com/mysql/mysql-docker/blob/mysql-server/5.7/docker-entrypoint.sh#L98-L105). You can create your SQL file that has UPDATE mysql.user SET Host="%" WHERE User='root'; in it and then ADD that file to /docker-entrypoint-initdb.d/ in your own image. Then, when starting a container based on that image it will initialize that SQL file.

Answer 2

That image specifies a default volume to hold the MySQL data at https://github.com/mysql/mysql-docker/blob/mysql-server/5.7/Dockerfile#L11. When you start the container, a volume is created for that container. When you update the permissions for the root user, it is saved in this volume (it is actually part of MySQL data for the mysql database). But once you remove the container, that volume is also lost.
There are usually two things you can do in this case to preserve the data between container restarts or even new containers:
Create a named volume and mount the data there. To do this you can run docker volume create mysqldata. Then, when starting the container mount the data with -v mysqldata:/var/lib/mysql. This volume will persist even after you stop or delete your MySQL container.
Bind mount the data to a host folder. Instead of creating a volume, you can just mount a folder such as -v /mnt/mysqldata:/var/lib/mysql. This will persist all your MySQL data on the host at /mnt/mysqldata.
Though, these are not the only ways to persist data, they are two built-in methods. There are also Docker volume plugins that allow you to use other storage mediums (examples might be https://github.com/rancher/convoy for NFS and https://github.com/NetApp/netappdvp for NetApp).

Answer 3

docker exec -it mysql bash
chown -R mysql:mysql /var/lib/mysql
if you change permission of volume in host, above code will correct permission denied for root.