Why can t I connect to AWS RDS

Question

0

I'm trying to connect to my new AWS RDS I just made. I followed the "Setting up for RDS" (https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_SettingUp.html), then the "Tutorial: Create an Amazon VPC for Use with a DB Instance" (https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_Tutorials.WebServerDB.CreateVPC.html), then the "Creating a MySQL DB Instance and Connecting to a Database on a MySQL DB Instance" (https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_GettingStarted.CreatingConnecting.MySQL.html) but I'm not able to connect to my DB from my computer or my dedicated server on the web.

Following the previous docs, I have this config :

My DB instance 

The VPC 

The subnetworks 

Example of subnetwork's details : 

The first security group : 

The second security group, calling the first one : 

For the first security group, I put both my private IP and the IP of my dedicated server, and their ports. I even tried to put 0.0.0.0/0 for SSH and TCP, it didn't work either.

For the DB instance, I tried to add the two security group instead of only the db-securitygroup, it didn't work. I tried to use a different Port for the DB instance, it didn't work.

With MySQL Workbench or with PDO on my dedicated server, I'm unable to connect to the DB : "SQLSTATE[HY000] [2003] Can't connect to MySQL server on [...]"