Clients showing as server IP address internally

[cr.mark]

We're in the process of replacing our old OpenVPN server with a new one.

I'm trying to figure out the difference between that setups that would be causing this (my guess is the new server is using topology subnet and old was net30).

If I connect using the new OpenVPN connection to one of our internal network eg. another linux server it will show my connection's IP address as the OpenVPN server's IP address.

If I do the same using the old OpenVPN connection it will show the OpenVPN client's subnet IP (10.15.*.*). Obviously for troubleshooting purposes, etc it's much easier if it shows this.

Can someone please point me in the right direction? Thanks!