NGINX redirect from main site to gray IP on port ??

Question

Nginx

Good afternoon. Tell.
There is an organization website like www.site.com/blablabla - there is a PHP script that just parses pre-loaded text files, no sessions, nothing like that, it just gives the parsing result when accessed.

There was a need to transfer the parser to a separate VM. You can just give the VM a white IP and attach a subdomain, but it seems to me that there is a more elegant solution:

Attach a gray IP address (172.16.

Let's say www.site.com:8081 would take data from VM 172.16.0.10 and open the plate generated by the parser.

If this is possible, and I think it should be, then
two questions:
1) Do you need the Internet on the gray IP address, and just redirect to it,
or will NGINX just take the data and display it on the external site normally (preferably)?

2) What is the name of this construction in NGINX to google articles?

Answer 1

1) Not needed
2) It's called proxy_pass