7 Steps for troubleshooting connection issues

troubleshooting

#1

Ah, yes, the “I hit a URL and it doesn’t respond error.” One symptom for 20 possible underlying causes :slightly_smiling_face:

You need to methodically go through and eliminate possibilities:

  1. Is your app running on some EC2 Instance / ECS? If you SSH to the app’s server, can you test it over localhost?
  2. If yes, can you reach the app via its private IP from another EC2 instance in the same VPC?
  3. If yes, is it configured to register with the ALB?
  4. If yes, are the ALB health checks passing?
  5. If yes, what routes or domain names is the ALB configured to send to the app and are those the routes you’re testing?
  6. If yes, does the ALB security group allow inbound connections?
  7. If yes, is the domain name configured to point at that ALB?