Can't connect to RDS instance from EC2 instance

Question

From EC2 instance i-78a8df00, I\'m trying to connect to RDS instance mysql.************.us-east-1.rds.amazonaws.com. They are both in the U.S. East region. I added the secur

Answer 1

While Mark's problem seemed to have something to do with multi-AZ routing & EC2 classic, I ran into this exact same problem today.

To fix it, I modified the Security Group that was created automatically with my RDS instance by adding the two private IP addresses from my EC2 instance.

This was a fairly obvious problem, but I'm new to AWS in general, so hopefully this is useful for others like myself.