Chapter 17: Publishing Through Oracle Cloud Network Load Balancer

A Network Load Balancer (NLB) helps distribute traffic across multiple backend servers, ensuring high availability, redundancy, and scalability for your application. In this chapter, you’ll learn how to create a basic NLB setup to forward traffic to a backend service (e.g., Ghost).

Creating an NLB in OCI

1. Navigate to Networking → Load Balancers

In the Oracle Cloud Console:

Go to Networking
Click Network Load Balancers
Click Create Network Load Balancer

2. Basic Configuration

Name: e.g., hexacats-nlb
Compartment: Choose your compartment
VNIC Selection: Use existing subnet (preferably public subnet)
IP Address Type: Public (or private if internal-only)

3. Listener Configuration

Name: e.g., http-listener
Port: 80 (for HTTP) or 443 (for HTTPS)
Protocol: TCP
Backend Set: Create new (next step)

4. Backend Set Configuration

Name: e.g., ghost-backend
Policy: Round Robin or IP Hash
Health Check Protocol: TCP
Port: 8080 (or the internal port your app uses)
Interval/Timeout: default (or lower for faster detection)

5. Add Backend Servers

Add your instance(s) by IP address or instance OCID
Port: 8080 (assuming that's where Ghost is running internally)

6. Security Configuration

Make sure the network security groups or security list allow:
- Inbound traffic on port 80 or 443 to the NLB subnet
- Inbound traffic from NLB to backend servers on port 8080

7. Create and Test

Click Create Network Load Balancer. Once provisioned:

Access your public IP to test:
http://<nlb-public-ip>
It should forward traffic to your Ghost container.

If you're using a Network Load Balancer and want to use Nginx as a reverse proxy, continue to the next chapter.