ERPNext cluster project

Hi,

Can someone help me with my issue?

I am working on an ERPNext project. My setup involves having all components and tools of the ERP in the internal network, with only the Nginx service moved to the DMZ.

What I did:

Installed ERPNext on one internal server. I am able to access it without any problem (includes nginx).
Installed a new Nginx service on my Ubuntu server in the DMZ.
Copied the configuration and pointed the server to my internal network on port 8000.
For now I am working on this guide, I am trying to install proxysql just to point the internal server properly
https://medium.com/@serverfabric.tech/erpnext-high-availability-setup-with-galera-and-proxysql-a0fcb9a1e5f

Kindly advise. Thank you so much

upstream frappe-bench-frappe {
server :8000 fail_timeout=0;
}

upstream frappe-bench-socketio-server {
server 127.0.0.1:9000 fail_timeout=0;
}