I'm trying to deploy php web app(contained in docker image) acompanied with instance of mysql and instance of redis. Public access is required for app instance, but not desired for database and redis. I followed this tutorial, but it seems a bit outdated and I had no luck.
I did create:
What I don't understand is interaction between these instances and parameters of their SecurityGroups. I could create EC2 instance and host all services there, but that's not the best way to use aws. Perfect solution would be example CloudFormation template, since down the road I will need multiple such implementations, but any other info, that points me in the right direction will be apreciated.