Port forwarding from vpn to lan

Hi there, I’ve read thru these topics and seen some indication that setting up a port forward in the GL-iNet firmware of my MV1000 from External Zone of ‘ovpn’ port 5000 to Internal Zone of ‘lan’ port 5000 should work, where by “work” I mean:
I want to forward connection attempts from the Internet to port 5000 on the OpenVPN endpoint, to port 5000 on the host I specified in the port forward; however, it doesn’t work.
The first thing I notice is that there doesn’t appear to be anything listening on port 5000 on the OpenVPN endpoint: I run ‘netstat -an’ and there is nothing. Is this an indication of a problem?
That leads me to a broader question, is it actually possible for an OpenVPN client to say “hey server, I want to listen on your port 5000” and for this request to be honored? I’m pretty new to VPN in general. This is on a Linux-based OpenVPN endpoint which I control - but I’m wondering if default settings may be preventing my attempt to forward a port.

That’s probably possible, but instead you could set up a site-to-site VPN so that machines on either side of the tunnel can route directly to each other, using their private/local IP. That way, you don’t have to mess with rules for individual IPs and ports.

First I think it should work. You will need to access from your vpn server in your scenario, not from the Internet.
Second, you set up portforward but it does not mean there is something listening on port 5000. Why do you want to port forward port 5000? You should have something running on 5000 for purpose.

I’ve gotten this partially working, set up port forwards from ovpn to lan. The problem is that the port forward seems to only work for the first connection, then it becomes unavailable to subsequent connection attempts from the same host or a different host for some period of time. I haven’t been able to figure out what’s causing this.