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