One white IP - several virtual machines?

Question

Computer networks

Good afternoon, there is a server with windows server, 1C is spinning on it. There is one white ip, you won't be able to buy more.
I would like to run a few more virtual machines on it, but in such a way that I can access each of them from the outside. On one, let's say, for telephony to work, on the other - internal sites were spinning, on the third, wrap the fish.
They will have different assignments, working ports and all that, too.
It is clear that since there is only one IP, you will have to create different domain names for them, by which the server will determine the request path.
Well, for example, pbx.example.com, 1c.example.com, corp.example.com
So, is it possible to make the main server work as a router, and when requested, for example, in pbx.example.com, it all requests via any ports sent vm with telephony,
At the request of corp.example.com - on vm with sites
At the request of 1c.example.com to process it yourself?
I know that web servers like nginx work like this, but how can I do it at the vm level?
Thanks in advance!
Ps. There is no access to the router, it is a separate server.
Ports can overlap

Answer 1

if you have services on different ports, it's easier to set up port forwarding on a regular router, to different internal ip. matching ports can be shifted on the external interface. if there are not many services, it will be much easier, faster and cheaper. and you can do with one name

Answer 2

On one external IP and port (80 and 443) (regarding the HTTP(S) protocol) - you can plant as many domains as you like, because the domain name is sent in an HTTP/1.0 packet and this can be proxied by the web server to different internal IP addresses.
Entry points (to an external IP address) can be made different (or all listed together) and tied to different internal IP addresses (regular or virtual machines):
srv1.example.com
srv2.example.com
example.com
example.com/ srv1
example.com/folder/srv1
Also, regarding domain services, there is an SRV field in the DNS, where for each protocol you can specify the target host, port and priority: link
PS: Instructions for setting up a proxy on Apache (Digital Ocean): here .

Answer 3

Your task was easier for me...
Proxmox - install virtual machines.
Make one virtual machine a router. The rest of the machines under the necessary services. As already mentioned, forward ports from "services" to "router".
Moreover, web services can be skipped through nginx.
I also had OpenVPN on my "router" and I connected to separate internal virtual machines.

and when requested, for example, in pbx.example.com, he sent all requests on any ports to VM with telephony,
At the request of corp.example.com - to VM with sites
On request of 1c.example.com to process it himself?

As already said, you can hang up on one name, but you can, as you wrote .... all names will still refer to one IP.
With telephony it is necessary to check .... I have doubts that there will be enough "power".
It was easier for me - there were a lot of white IPs, I did what I wanted :)
48 GB of RAM and a 2-stone ML350 - this is a question of power. What do you have?