Docker mysql change password

Question

My docker-compose look like:

version: '3.4'
services:
  mysql:
    image: mysql:8.0
    command:
      - --default-authentication-plugin=mysql_native_password
    volumes:
      - ./mysql-data:/var/lib/mysql
    env_file:
      - .env
    ports:
      - 3306:3306

My.env file look like:

MYSQL_ROOT_PASSWORD=root
MYSQL_DATABASE=db
MYSQL_USER=user
MYSQL_PASSWORD=user

Now if I change the password in .env file, it does not change the password in the docker container after the restart. I suppose that happens because I have mapped volume from host to container and I think there are all settings saved.

My question is: How can I change the password for mysql, without modyfing or deleting mysql-data folder?

Answer 1

You can log in to the MySQL shell inside the container and then manually change the password following any standard MySQL guide.

To log in to the container, execute docker exec -it <container-id> mysql -u root -p and provide the root password when prompted. After logging in, you can follow this guide to change the password: How to reset the root password in MySQL 8.0.11?

To log in to the container shell (not MySQL shell), execute docker exec -it <container-id> bash .