Is it possible Private EC2 Instance send outbound traffic to Public ELB?

Question

Here is the AWS structure I created.
- VPC : 1
- Public Subnet : 2 (1 EC2 Instance in each Subnet)
- Public ELB : 1 (About Public Instance)
- Private Subnet : 1 (1 EC2 Instance)
Here, I want to make a request to the Public ELB from the instance in the Private Subnet. How can I do this? Or did I get the structure wrong?

Answer

If you're accessing a Public load balancer that is in a different VPC (owned by you or by someone else) then the answer from Jhalak is correct - [NAT Gateway](https://docs.aws.amazon.com/vpc/latest/userguide/vpc-nat-gateway.html) is the way to go.

But I think your question is asking how you access the load balancer in the same VPC. You can still use NAT Gateway but there is a charge associated with that. Today, there's no simple way of getting a DNS record for the private IP of the load balancer. Instead, you might create a second private load balancer.

Also: Your question mentions ELB; please consider using ALB as it has many more features.

Answer

you can use NAT Gateway to send traffic out of your Private EC2/subnet.

Is it possible Private EC2 Instance send outbound traffic to Public ELB?

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