Unable to Connect MySQL container to Tomcat Container in docker

Question

The Plan

I want my tomcat server to be able to connect to my MySQL server both in separate containers.

The Problem

Answer 1

As you're linking db as "db", you cannot use localhost to join you database. you should "db"

jdbc:mysql://db:3306/tracker?useSSL=false

In your container, localhost design your tomcat container, not your host. MySQL container has his own network.

Futhermore, if you don't like "db" name, you can name link it with different name

For exemple:

 links:
   - db:container-mysql

In this case, inside you tomcat container, you could use

jdbc:mysql://container-mysql:3306/tracker?useSSL=false