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I am going to maintain a list of tips for anybody that wants to host a fsx multi-player session.



The up to date list can be found here.





Currently the list is.



  • Use a dedicated machine with fsx to be a host. Host using a control tower as this consumes less resources then a plane.
  • Use the standard ports of 6112 to 6122. There is no reason to change them and fsopen server ony supports this range anyway.
  • The only inbound changes to your router's firewall or antivirus software firewall is to allow UDP 6112 to 6122. Another reason not to change from the defaults. If you don't do this your session will be listed in red in gamespy. All other connections are outbound only and this is normally allowed by default for firewalls.
  • On your server turn all the detail down to minimum and 10 frames per second.
  • Go to speedtest.net or similar and check the bandwidth for your servers connection. Upload speed is the most important for hosting and is commonly only about 1Mbit. Every player that joins needs about 50Kbits which means 1Mbit will only support about 20 users before packets are dropped. More sessions are now using 128k voice but this means you will need about 150kBits per user. Yes the voice is much better but 1Mbit will only support 7 players.
  • Watch out for non standard fsx planes. Some were not made with multiplayer in mind and can transmit 10 times (or more) network traffic. If you have 1Mbit upload just one of these planes can result in your server being overwhelmed. FSopen server can be tailored to kick these planes as appropriate.
  • Don't forget about everthing else using your internet can kill your session. If your girlfiend is watching youtube she'll be eating up your upload bandwidth. As a rule of thumb, whatever speed you download at, 5% - 10% is required as upload. Obviously torrent software can kill connections. Don't use it!
  • If upload speed is limited consider getting a router that offers good QOS (Quality of service). I bought one that lets me reserve a fixed amount of upload bandwidth for UDP 6112-6122. Doesn't matter what anybody starts doing then.
  • Upload speeds are key to good sessions. High speed interenet is rolling out and some of the upload speeds are just awsome! If you're really serious look at hosting with an isp but that's very expensive.
  • Where bandwidth is tight, disable the sharing of aircraft.


Please let me know if you have any other useful tips that should be on this list or if you disagree with anything.


Is this useful to anyone reading this?



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A few other things you might like to add to your list.


(1) Server UPLOAD Bandwidth goes up as the SQUARE of the number of Players.

Since Internet Upload Bandwidth is often low, compaired with Download Bandwidth, the UPLOAD bandwidth of the SEERVER becomes the critical factor in how many players can be hosted.


ie If 10 player needs 1 Mbps,

doubling the players to 20, now require 4 Mbps,

40 players = 16 Mbps ( Not many hone Internet connects support this)

80 players = 64 Mbps ( Now you are looking a Co-Location Hosting on a 100Mbps pipe !!)


(2) Having set the Hosting server to run, then call up MAP mode, and leave it there.

This will turn off all the Server's processing of 3D Video, and the CPU usage will drop dramatically, from say 80% down to 5% or so.


(3) Make sure you have the Latest version of FSUIPC on your Hosting machine.

It does not need to be a Registerted Install, but even in unregistered mode, it will filter out most g3d.dll errors that can be randomly generated by FSX, causing the session to Crash.



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Additional Tip:


If Running a FSX MP Server under Windows 7, and you have it connected to gamespy, then be sure to set FSX to run in XP SP3 Compatability mode.


It should prevent an apparent bug inb FSX, that causes it to randomly disconnect from the Gamespy Server.


(Disconnects may happen in less than an hour, or as long as a day)

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