So I'm using an L2TP/IPSec VPN service which allows me to forward ports so I can access servers on my local network from the public internet. This works great when I've got my Windows PC as the client with its firewall disabled. I can see that my ports are open and my running services are accessible. However, now I'm using my Mikrotik router as the L2TP client having followed the tutorial here (using L2TP instead of PPTP).
I've setup NAT masquerade, configured the mangle and routes and all my network traffic is now being routed via the VPN and it works great except that I'm not able to see my open ports any more. Everything else is configured as default. I've tried to configure dst-nat but to no avail. I guess what I'm asking is how can I port forward on a VPN interface or more specifically, how can I access Plex when it's running behind a router which is working as a VPN client? (My VPN service supports port forwarding). Cheers.
Flags: X - disabled, I - invalid, D - dynamic 0 ;;; defconf: masquerade chain=srcnat action=masquerade out-interface=ether1 1 chain=srcnat action=masquerade out-interface=VersaVPN log=no log-prefix=""
Flags: X - disabled, I - invalid, D - dynamic 0 chain=prerouting action=mark-routing new-routing-mark=L2TP passthrough=yes src-address=192.168.88.2-192.168.88.254 log=no log-prefix=""