Configuring the NGINX Server - HTTPS Virtual Hosts / Load Balancing / IP Access Restrictions

First, we'll need to become the root user:

sudo su -

Let's verify that the X509 certificate was correctly generated using the openssl verify command:

openssl verify -CAfile /etc/nginx/ssl/bigstatecollege.edu/ca-cert.pem /etc/nginx/ssl/bigstatecollege.edu/server-cert.pem

We should see the following:
server-cert.pem: OK

Configure the bigstatecollege.edu virtual host to use HTTPS:

cd /etc/nginx/sites-available

vi bigstatecollege.edu.conf

Change the listen line from port 80 to 443, and add ssl after 443:

listen 443 ssl;

Add the following lines after the server_name configuration line:

        ssl_certificate /etc/nginx/ssl/bigstatecollege.edu/server-cert.pem;
        ssl_certificate_key /etc/nginx/ssl/bigstatecollege.edu/server-key.pem;

Save and exit.

Validate and reload NGINX:

nginx -t

systemctl reload nginx

Test the new HTTPS connection. We will need to use the --insecure switch in order to accept the self-signed certificate:

curl --insecure https://www.bigstatecollege.edu

We should see Welcome to www.bigstatecollege.edu!.

Congratulations! The virtual host for bigstatecollege.edu is now configured to use HTTPS.

There's already an upstream group configured in the bigstatecollege.edu virtual host. Remove the backup status from app2 and app3. This will make them live. Edit the bigstatecollege.edu.conf file:

vi bigstatecollege.edu.conf

The end result should look like the following:

upstream bscapp  {
   server app1.bigstatecollege.edu:8085;
   server app2.bigstatecollege.edu:8086;
   server app3.bigstatecollege.edu:8087;
}

Save and exit.

Validate and reload NGINX:

nginx -t

systemctl reload nginx

Test the new configuration for https://www.bigstatecollege.edu/app:

curl --insecure https://www.bigstatecollege.edu/app

Reload the command several times. We should see Welcome to app1.bigstatecollege.edu!.

We're going to restrict the bigstatecollege.edu virtual host to the 127.0.0.1 interface. Add the following lines after the listen 443; line in the bigstatecollege.edu.conf file:

        allow 127.0.0.1;
        deny all;

Save and exit.

Validate and reload NGINX:

nginx -t

systemctl reload nginx

Test the new configuration for https://www.bigstatecollege.edu:

curl --insecure https://www.bigstatecollege.edu

Access is forbidden via the private IP address. Try to access the virtual host via localhost:

curl --insecure -H "www.bigstatecollege.edu" https://localhost

We should see Welcome to www.bigstatecollege.edu!.