Short Notes on AWS

Can't connect to EC2 instance

The obvious 2 problems with incoming requests, that are outside of AWS's scope:

check the instance's firewall
check that the app is listening to all incoming (0.0.0.0/0 or your IP, not just 127.0.0.1)

On the AWS side, check the following:

make sure the Elastic IP is associated with the instance
- find the instance in the EC2 > Instances
- look under Description tab, Elastic IP
- if it's not, go to EC2 > Elastic IPs
- choose Elastic IP from the list (or, allocate new on) that is not associated with any instance
- choose Actions > Associate address, and associate it with the instance
make sure Security group permissions allow the connection
- go to EC2 > Security Groups
- select the security group (you can find which security group instance is in in the list on EC2 > Instances page, last column)
- on the Inbound tab, check that your protocol is enabled for Source 0.0.0.0/0 (or from your IP)
make sure your Internet Gateway is connected to your VPC
- make sure the Internet Gateway is attached to your VPC, under VPC > Internet Gateways > Summary tab
- go to VPC > Route Tables, select route table for your VPC
- under Routes tab, make sure that route with destination 0.0.0.0/0, with Target being your internet gateway, exists and is Active

you need policy AmazonRDSReadOnlyAccess for your IAM to be able to list RDS instances