So let me see if I understand your setup and what you want to accomplish. Please correct me if I'm wrong, but your network looks something like this, right? I'm using a.b.c.184/29 as an example IP block for the 5-static setup (/29, 5 usable addresses) and 10.0.0.1/24 for the LAN. Just replace those with whatever your /29 block is and whatever LAN RFC1918 addresses you want to use.
SMC(WAN iface=a.b.c.190)
|
(external NIC=a.b.c.185, aliases for a.b.c.186-a.b.c.189)
|
pf_sense
|
(internal NIC=10.0.0.1
|
switch_or_wap
| |
(nat) other clients...
|
|
windows(NIC=10.0.0.100)
And what you're doing is trying to connect to the windows box @ 10.0.0.100 on your LAN via one of the public IPs (a.b.c.185 - a.b.c.189) via port 3389?
What you need to do is the following:
1. Set the SMC into "true static" mode in which you disable all NAT, DHCP, firewalling, etc. This is important so that you aren't doing double NAT and don't have to fiddle with the SMC to forward ports or unblock firewalled ports.
2. Set the pfsense box's default gateway to a.b.c.190 and assign a.b.c.185 to the external NIC on the pfsense box
3. Set the pfsense box's internal NIC to some RFC1918 address/subnet (e.g. 10.0.0.1)
4. Run DHCPD on the pfsense box's internal NIC for the LAN subnet you choose or use statically assigned LAN IPs for all your device(s) if you so choose. YOu can set dhcpd to hand out the same IP each time by MAC address, which is what I do. So my IPs are obtained via DHCP, but are always the same IP.
5. Setup pfsense to forward port 3389 from a.b.c.185 to the LAN at 10.0.0.100 (or whatever IP you get from DHCPd or assign statically to the windows box either manually or via DHCP)
6. Ensure port 3389 is allowed on pfsense inbound for a.b.c.185.