Server on one machine, FS on another

Started by Hippo, April 16, 2007, 03:22:44 PM

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I know you covered this in the Features section (see post but I have the same issue.  I have tried the suggested option you provided to Danzian but cannot get it to work.

It's actually more complicated because I can join or be joined by some players on my host but not others.  Yet I can join or be joined by those unable to connect to my host on another Host server (we've used Rory Gilles Shetland Flyer to test this).  This suggests problems routing locally for me yet I know there is an issue between players joining my host.

Currently I have the following forwarded to the FSHost PC:
TCP Port 80
UDP 23456
UDP 6073
UDP 23432 (for FSNav users)
UDP 23422 (for ATC Radar Screen 5)
UDP 2302-2309 forwarded to 2302
UDP 2310-2319 forwarded to 2310
UDP 2320-2329 forwarded to 2320
UDP 2330-2339 forwarded to 2330
UDP 2340-2349 forwarded to 2340
UDP 2350-2359 forwarded to 2350
UDP 2360-2369 forwarded to 2360
UDP 2370-2379 forwarded to 2370
UDP 2380-2389 forwarded to 2380
UDP 2390-2400 forwarded to 2390

UDP 23455 to FS2004/FSX machine

Any further ideas? I've e-mailed Rory and he says he'll look into his routing set-ups for me, if this throws anything up, I'll post it here for others to see.

Paul Reynolds

Russell Gilbert

Hi Paul,

Yeah, this is a tough problem, getting FSHost and FS working on separate machines from the same LAN.  DirectPlay just doesn't handle it very well.

It looks like your list of ports is ok, but I'm not sure what you mean by, "UDP 2302-2309 forwarded to 2302", etc.  Normally you'd just forward the whole range of 2300 to 2400 to the FSHost machine's internal IP address (or 2302 - 2400 if only supporting FS2004).



The thinking behind the UDP 2302-2400 being routed in groups was routing to one port (2302) is a many to one, preference would one to one but forwarding this was not possible for so many ports.  I reasoned that if the connection problem was on these ports then forwarding them in groups may resolve the issue.  I have now reverted to 2302-2400UDP being forwarded to 2302UDP only.

While I'm on this topic, I also fly on-line through the Pilot Club.  With 23456UDP and 6073UDP forwarded to the FSHost machine, this was causing problems with seeing other players on the Pilot Club network.  I resolved this with the following:

FSHost machine
23456UDP local to 23457UDP remote
6073UDP local to 6074 remote
2302UDP local to 2402 remote

23457UDP local to 23456UDP on FS2004 machine
6074UDP local to 6073UDP on FS2004 machine
2402UDP local to 2302UDP on FS2004 machine

This effectively means the FSHost machine receives the data on 23456, 6073, 2302UDP the passes it on to the FS2004 machine without the router objecting.

Russell Gilbert

Aha, ok.  So your router doesn't support forwarding a range of ports (2302 to 2400).  Well, in that case I'd suggest just forwarding the first few, like maybe 2302 to 2306 -- that'd give it 5 ports to work with, and since it tends to use the lowest numbered port first (although I don't know if that's always guaranteed) it'd probably work out ok.  Especially since the 2302-2400 range is sort of a backup set of ports for FS2004 anyway, because it has the new 23456 port that it tends to use when it can.

I'm not sure I completely follow how you're forwarding it to both machines, but I guess if it works, it works.  Is it all working now?



Let me try to explain the forwarding a little better.  a Packet comes in from ISP on 23456UDP, the router sends it to FSHost PC as normal. I then set the  FSHost PC to forward data on 23456UDP to the port 23457UDP on the FS2004 machine but as this would go via the router, it intercepts data on 23457 and sends it to port 23456 FS2004 machine.


Packet from ISP on 23456 (6073) (2302-2400)
     |    |     |      |    |    |     |      |     |     
     v    v     v     v    v    v     v     v     v   
Router forwards 23456 (6073) (2302-2400) to FSHost PC (2302-2400 on port 2302)
     |    |     |      |    |    |     |      |     |     
     v    v     v     v    v    v     v     v     v   
FSHost machine gets data then forwards to FS2004 machine on 23457 (6074) (2402)
     |    |     |      |    |    |     |      |     |     
     v    v     v     v    v    v     v     v     v   
Router intercepts data on 23457 and forwards it to FS2004 machine on 23456 (6073) (2302)

This hasn't completely resolved my set-up though it did allow access for at least one flyer who could not previously get in. I'll try your suggestion of adding 2303-2306 later, that may resolve things.

Paul Reynolds

Russell Gilbert

Hmm, ok.  I think I get what you're trying to do.  But I think you'll continue to have problems if some of the ports aren't making it to each machine.  For example, if the FSHost PC forwards ports to the FS2004 machine, I'm assuming that FSHost will never see that incoming data, which will be a problem.

Wish I had a solution for this, I know a lot of people have tried to get it to work, but I think DirectPlay just wasn't really designed to handle it very well.  But let me know if you find something.



I understand that Russell, for me there is an equivalent, musicians would be aware of midi in, out and through.  I have effectively mimicked the through which is to say the host machine picks up the data but also passes it on.  It may work on some set-ups but not on others, it was the same with midi systems. At least by sharing we can provide options for others to try.

Paul Reynolds


I think I have a similar set-up (FSHost on one machine and FS9 running on another) and it doesn't seem to create the same problem. i.e. I don't have a problem.

It works like this:

Traffic from the outside world hits an XDSL modem which forwards incoming packets on ports 80-84, 2302-2400, 6073, 23450-23456 to an internal broadband router and sends packets back to whatever IP address they came from.

The internal broadband router is set up to forward all incoming packets on ports 80-84, 2302-2400, 6073, 23450-23456 to the machine running FSHost. So when another PC on the internal network sends packets to the broadband router they automatically get forwarded to the PC running FSHost.

The FSHost machine receives packets and sends replies back to the broadband router.

The broadband router returns packets to the originating address (either towards the PC on the internal network running FS9 or towards the XDSL modem)

The XDSL modem then forwards packets back to the correct outside world address.

So what I want to say is that I didn't have to do any special tricks to route external and internal traffic to the right PC. The broadband router is intelligent enough to figure out where each outbound packet has to go to.

The major difficulty I encountered was figuring out that from the XDSL modem I had to port forward the incoming traffic to the broadband router (and not to the PC running FSHost) and in the broadband router I had to forward incoming traffic to the PC running FSHost (this is somewhat contrary to the instructions given on



Traffic from the outside world hits an XDSL modem which forwards incoming packets on ports 80-84, 2302-2400, 6073, 23450-23456 to an internal broadband router and sends packets back to whatever IP address they came from.

I understand where you're coming from but I'm using an eTec 8505g which is a combined ADSL2/2+ router and modem.  I cannot see how I can forward ports specifically from the WAN side to the routers internal address rather than directly to the FSHost machine.

If you want to look through the manual for my router and make any suggestions, I'd be more than happy to give it a whirl. The manual gan be got from


Hey Hippo, Sorry for the long delay in replying (only just read your question).

The explanation you asked about starts on page 61 of your manual. You may also find easier instructions on but you have to do it for all the ports (80-84, 2302-2400, 6073, 23450-23456)


I run fshost on one machine and fs9 on another behind a firewalled router.  I use 23456 exclusively for FS9.  FSHost is a different application, so I assign it a different port.  I have set FSHost to receive input on 23556 (not 23456) and set my router to forward packets to 23556 to the FSHost machine.  I can connect my own FS9 via the LAN without setting any ports for that. By doing this, I can still do peer to peer FS9 connectiosns if i want to on 23456.  When connecting to Vatsim using FSInn there are no isssues with port conflict either.

This all works perfectly for connections with the correct ports forwarded.