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dnscontainersamazon-ecs

DNS to ECS containers

I have an ECS cluster in which I run a task with many container. Three of them need to be reached from the internet. These container are exposed on port 80, 8080 and 8880 of the cluster's ec2 instance. I have a DNS name registered (say example.com), and I can create a CNAME record that points to the ec2 dns name, but if I do so, the app will be reachable as

  • example.com:80
  • example.com:8080
  • example.com:8880

Instead what I would like to do is to reach the three container like this:

  • app1.example.com (instead of example.com:80)
  • app2.example.com (instead of example.com:8080)
  • app3.example.com (instead of example.com:8880)

I can't do it with the DNS CNAME because is not possible with CNAME to redirect to specific ports.

I hope the question make sense. Any suggestion from anyone would be appreciate. Thanks in advance!

Solution

  • You will need to place an AWS Application Load Balancer in front of the ECS containers in order to accomplish this. You would have 3 different target groups (one for each container) and configure the Load Balancer to use host-based routing to send the traffic to the appropriate target group/container.