Mass Disconnects - TCPBuffer error.

Discussion in 'Hosting Help' started by TheSecret1, Jun 23, 2023.

  1. TheSecret1

    TheSecret1 Registered

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    we do Broadcast, but the broadcast happens on a separate machine that is currently turned off.
    It is a private machine that connects via spectator.
     
  2. Chris M

    Chris M Registered

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    Surely blocking port 80 shouldn't influence the outgoing connections rf2 is generating on port range 50000-65000, even if the destination is ultimately port 80

    Can anyone from S397 around here confirm why their software wants to connect to google cloud? We had a massive number of time_wait connections the other night (hundreds every second) with blocks of driver disconnections mid event, as seen during the Virtual Le Man's 24Hrs. Logs indicated TCP buffer overflows.

     
  3. Goanna

    Goanna Registered

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    Dunno Chris, I followed this https://learn.microsoft.com/en-us/w...windows-firewall/create-an-outbound-port-rule to block outgoing ports where they say to use the remote port, ie in this case port 80. I’ve created a windows defender rule on our server to block port 80 and even though rF2 is sending them out on various different ports they’re resolving to the Google site on port 80. As I said in my previous post tcp connections dropped from 500 to 20. It would be interesting to hear from devs why rF2 is trying to connect to Google in the first place.
    Edit: tagging @Coutie perhaps you can ask devs please.
     
  4. I'm quite interested in how you have set up this server, if it is indeed a dedicated server and who installed windows etc. I hardly see above 3-4 connections when i test it (obviously without any race going on). Both on Windows Server 2021 rev 2, Windows Server 2016 and Windows Server 2019 (all with latest updates). Same with rF2 - latest build.
    I dont see a single connection to google or google cloud.
    Usually there is no reason to block outgoing traffic from a server, unless you really know what you are doing. It really looks like you are running some sort of plugin/page/something on port 80.
     
  5. Goanna

    Goanna Registered

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    Hi Jimmi, In my case the os (windows server 2019 standard) was installed by our host, I keep it updated, rF2 server is a steamCMD server (BuildID 11262536) and the only plugins we have running are as follows, none of which I believe use port 80.
    plugins.PNG

    All the extraneous tcp connections only start when the dedicated server is started and stop as soon as the server is closed
    Screenshot is of some of them(port 80 not blocked);
    Capture.PNG

    This is all tcp connections on the box (port 80 blocked);
    allrunningnetwork.PNG
     
  6. How does it look with liveracers, sharedmem and welcome message removed?
    A different note: you should ask your host to block 3389 on their firewall (before your machine) to your ip only though. Windows server 19 is not that good on filtering out those bots hammering on the port. Not relevant though, just saw different ip´s on 3389 on the list above.
     
  7. Goanna

    Goanna Registered

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    Same tcp connections.
     
  8. TheSecret1

    TheSecret1 Registered

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    @Jimmi Allison - everything @Goanna said is the same for us.

    Our host Servers Australia installed Windows 2019 for us.
    Additionally we have turned all plugins off and get the same TCP Connections.
     
  9. Chris M

    Chris M Registered

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    Just to further the discussion on this subject, I noticed the moment I execute 'rFactor2 Dedicated.exe' and before I commission a server for use (even with all plugins disabled), the executable is already trying to make hundreds of concurrent outbound connections to google servers on port 80, all with different internal port numbers.

    I observed that if I block these google servers via windows firewall, the outbound connections stop, it doesn't appear to adversely affect our ability to host our server, but we get the following error in the trace log file.

    NetCommDedic 5531: Server disconnection from network detected.

    When I reopen the firewall to these google servers, the error messages disappear.

    I guess the question is, if this has a legitimate purpose for rfactor2 dedicated.exe; what's it's purpose and, why does it need to open a new connection on a new port, every second?
     
    Last edited: Sep 5, 2023

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