connecting to a docker-compose mysql container denies access but docker running same image does not

Question

I am having some issues connecting to the mysql docker container that I have launched with docker-compose. This is a long post (sorry!).

Here is my docker-compose.yml file:

db:   image: mysql:5.7   ports:     - "3306:3306" # I have tried both ports and expose "3306". Still doesn't work    environment:     - MYSQL_ROOT_PASSWORD="secret"     - MYSQL_USER="django"     - MYSQL_PASSWORD="secret"     - MYSQL_DATABASE="myAppDB" 

Then:

$> docker-compose build db uses an image, skipping #expected! $> docker-compose up <<LOTS OF OUTPUT>> 

OK, so now I have an up and running docker container runner mysql:5.7. Great! Or is it? When testing in my django app, I get Operational errors saying that the user isn't allowed to connect the database. Ok, so maybe it's my django then?

$> docker ps CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                    NAMES c7216f99ca0f        mysql:5.7           "docker-entrypoint.sh"   3 minutes ago       Up 3 minutes        0.0.0.0:3306->3306/tcp   sharpfin_db_1  $> docker-machine ip dev 192.168.99.100 $> mysql -h 192.168.99.100 -P 3306 -u django -p Enter password:  ERROR 1045 (28000): Access denied for user 'django'@'192.168.99.1' (using password: YES) 

ok so maybe It's something to do with connecting to the docker-compose container? What if I try connecting from inside the docker container?

$> docker exec -it c7216f99ca0f /bin/bash root@c7216f99ca0f:/# root@c7216f99ca0f:/# mysql -u django -p                                                                                                                                                            Enter password:  ERROR 1045 (28000): Access denied for user 'django'@'localhost' (using password: YES) 

ok, so docker mysql won't let me connect, don't know why. Let's see what happens when I try do this without docker-compose:

$> docker run --name run-mysql -e MYSQL_ROOT_PASSWORD="secret" -e MYSQL_USER="django" -e MYSQL_PASSWORD="secret" -e MYSQL_DATABASE="myAppDB" -p "3306:3306" mysql:5.7 <<LOTS OF OUTPUT SAME AS BEFORE>> 

Ok, so now we have a container running the same image as before with the same settings. (I think this assertion is probably not true - docker-compose is doing something different to docker run).

$> docker ps CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                    NAMES 73071b929e82        mysql:5.7           "docker-entrypoint.sh"   3 minutes ago       Up 3 minutes        0.0.0.0:3306->3306/tcp   run-mysql 

There's my container (called run-mysql). Let's connect!

$> mysql -h 192.168.99.100 -P 3306 -u django -p Enter password:  Welcome to the MySQL monitor.  Commands end with ; or \g. Your MySQL connection id is 2 Server version: 5.7.12 MySQL Community Server (GPL)  Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.  Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners.  Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.  mysql> SHOW DATABASES; +--------------------+ | Database           | +--------------------+ | information_schema | | myAppDB            | +--------------------+ 2 rows in set (0.01 sec)  mysql> 

Alright. Can log in. That's weird... What about from inside the container?

$> docker exec -it 73071b929e82 /bin/bash root@73071b929e82:/# mysql -u django -p                                                                                                                                                            Enter password:  Welcome to the MySQL monitor.  Commands end with ; or \g. Your MySQL connection id is 3 Server version: 5.7.12 MySQL Community Server (GPL)  Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.  Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners.  Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.  mysql> SHOW DATABASES; +--------------------+ | Database           | +--------------------+ | information_schema | | myAppDB            | +--------------------+ 2 rows in set (0.00 sec)  mysql>  

Ok, I can log in from outside and inside the container when I launch with docker run, but not with docker-compose. What's going on? There must be something either docker-compose is doing behind the scenes that changes how the database is initialized.

All the above is the exact same if I try with the root user as well. So it's not a permissions issue with the django user.

Any ideas how to resolve this?

Answer 1

Environment variables in docker-compose.yml file should not have quotes when using array definition:

db:   image: mysql:5.7   ports:     - "3306:3306"   environment:     - MYSQL_ROOT_PASSWORD=secret     - MYSQL_USER=django     - MYSQL_PASSWORD=secret     - MYSQL_DATABASE=myAppDB 

---

If you use them in your docker-compose.yml file:

db:   image: mysql:5.7   ports:     - "3306:3306"   environment:     - MYSQL_ROOT_PASSWORD="secret"     - MYSQL_USER="django"     - MYSQL_PASSWORD="secret"     - MYSQL_DATABASE="myAppDB" 

and run:

$ docker-compose up -d 

and enter running container:

$ docker-compose exec db /bin/bash 

you will see the output:

root@979813643b0c:/# echo $MYSQL_ROOT_PASSWORD                                                                                                                                               "secret" 

Answer 2

I had a similar issue, and this helped me:

https://github.com/docker-library/mysql/issues/51#issuecomment-76989402

Have you changed the passwords since you first tried running the containers? docker-compose does extra work to preserve volumes between runs (thus preserving the database); you may want to try docker-compose rm -v to delete everything and try starting it up again.