Keycloak suddenly can't connect to mysql javax.resource.ResourceException: IJ031084: Unable to create connection

I was running keycloak in docker all day yesterday at the office using these commands:

docker network create keycloak-network
docker run --name mysql -d --net keycloak-network -e MYSQL_DATABASE=keycloak -e MYSQL_USER=keycloak -e MYSQL_PASSWORD=password -e MYSQL_ROOT_PASSWORD=root_password mysql
docker run -d -it -e KEYCLOAK_USER=admin -e KEYCLOAK_PASSWORD=admin --name keycloak --net keycloak-network -p 8080:8080 jboss/keycloak

When I got home the keycloak started failing with

/opt/jboss/tools/docker-entrypoint.sh: line 165: DB_ADDR: unbound variable

I added the DB_ADDR env var

docker run -e DB_ADDR=mysql -e KEYCLOAK_USER=admin -e KEYCLOAK_PASSWORD=admin --name keycloak --net keycloak-network -p 8080:8080 jboss/keycloak:11.0.3

and it fails with

javax.resource.ResourceException: IJ031084: Unable to create connection

I’ve tried rolling back to 11.0.3 (version 12 was released yesterday) and tried adding

-e JDBC_PARAMS=useSSL=false

but still get the same error.

The only thing I can think of that changed was moving from my work network to my home network, but I can’t understand why that would be a problem when mysql and keycloak both run on the same docker network.

Is anyone else seeing this?

I was able to get this to work by using -e DB_VENDOR=mysql