title: Can't connect to RDS PostgreSQL DB instance through an RDS proxy
body: <p>I'm trying to put use an RDS proxy to pool and share connections established with an RDS database with a PostgreSQL engine. The problem is I'm able to open a connection to the DB, both through an ECS instance or in PgAdmin, however, I'm not able to connect through the proxy. To attempt a connection through the proxy in PgAdmin, I'm using the proxy endpoint as opposed to the DB endpoint but the connection attempt times out.</p>
  <p>I've successfully created the proxy and associated with my DB, both proxy and DB status is available. I've followed the <a href="https://aws.amazon.com/getting-started/hands-on/set-up-shared-database-connection-amazon-rds-proxy/" rel="nofollow noreferrer">example proxy setup</a> and the DB and the proxy are using the same VPC security group.</p>
  <p>Any ideas?</p>
  <p><a href="https://i.stack.imgur.com/LAtg8.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/LAtg8.png" alt="enter image description here" /></a></p>
  <p><a href="https://i.stack.imgur.com/7emUJ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/7emUJ.png" alt="enter image description here" /></a></p>