ssl certificate – How to use Nginx as a reverse proxy (HTTPS) for a self-signed (HTTPS) backend web application?

How to use Nginx as a reverse proxy (HTTPS) for a self-signed (HTTPS) backend web application?

I am asking this because I am totally confused about what to do…

All guidelines are welcome!

Network layout…

.-------------------------------------.
| INT_WEB_CLIENT                      |
|      ↕                              |
| NGINX_REVERSE_PROXY (HTTPS)         |
|      ↕                              |
| SELF_SIGNED_WEB_APPLICATION (HTTPS) |
'-------------------------------------'
  • The reverse proxy NGINX_REVERSE_PROXY uses a “Let’s Encrypt” certificate (Certbot);
  • The web application (backend) SELF_SIGNED_WEB_APPLICATION uses a SELF SIGNED certificate and due to its characteristics it necessarily needs a certificate (HTTPS) even if it is self-signed.

IMPORTANT: To be honest I don’t even know if what I’m proposing works or is the right thing to do. At the present time this seems the simplest to me.