Factorio Forums

Was hosting public factorio server yesterday and it desynced once.
Factorio server: 0.17.59 (headless)
Factorio client: 0.17.59 (steam)
OS: Ubuntu 18.04

I really can't help more than by sending the generated report, which probably is too large for forums to handle as when uploading, the status changes to "Error parsing server response." Instead, download it from my google drive: desync-report-2019-07-27_18-54-21.zip


Good amount of time later server also crashed while attempting autosave, but that's another issue and I don't have anything more than a few log lines:


heinä 27 19:32:25 olli-GA-970A-UD3 bash[21913]: 32893.424 Info AppManager.cpp:267: Saving to _autosave18 (non-blocking).
heinä 27 19:32:25 olli-GA-970A-UD3 bash[21913]: 32893.430 Error Util.cpp:83: Fork failed with errno: 12
heinä 27 19:32:27 olli-GA-970A-UD3 bash[21913]: 32895.465 Info ServerMultiplayerManager.cpp:114: Disconnecting multiplayer connection.
heinä 27 19:32:27 olli-GA-970A-UD3 bash[21913]: 32895.465 Info ServerMultiplayerManager.cpp:776: updateTick(4294967295) changing state from(InGame) to(DisconnectingScheduled)
heinä 27 19:32:27 olli-GA-970A-UD3 bash[21913]: 32895.814 Info ServerMultiplayerManager.cpp:138: Quitting multiplayer connection.
heinä 27 19:32:27 olli-GA-970A-UD3 bash[21913]: 32895.814 Info ServerMultiplayerManager.cpp:776: updateTick(4294967295) changing state from(DisconnectingScheduled) to(Closed)
heinä 27 19:32:27 olli-GA-970A-UD3 bash[21913]: 32895.933 Info HttpSharedState.cpp:54: Downloading https://multiplayer.factorio.com/remove-game/5707599
heinä 27 19:32:27 olli-GA-970A-UD3 bash[21913]: 32896.067 Info UDPSocket.cpp:218: Closing socket
heinä 27 19:32:27 olli-GA-970A-UD3 bash[21913]: 32896.067 Info UDPSocket.cpp:248: Socket closed
heinä 27 19:32:27 olli-GA-970A-UD3 bash[21913]: 32896.067 Info UDPSocket.cpp:218: Closing socket
heinä 27 19:32:27 olli-GA-970A-UD3 bash[21913]: 32896.113 Info UDPSocket.cpp:218: Closing socket
heinä 27 19:32:27 olli-GA-970A-UD3 bash[21913]: 32896.113 Info UDPSocket.cpp:248: Socket closed
heinä 27 19:32:27 olli-GA-970A-UD3 bash[21913]: 32896.115 Goodbye

That awkward moment when 87.63MB out of your 125MB save file are blueprints

The desync seems to have many moved belts inside blueprints and some different active transport lines, but i fail to figure out what caused it.

Investigation: The desync was triggered by mismatch in number of active transport lines. The desync happened ~5 minutes after the player joined the server, and more people got desynced (including ones that joined earlier and ones that joined later).
On the server items got backed up and transport lines were deactivated, the desynced clinet didn't have items on the transport line backed up just yet.
Around the area of desync, there are underground belts marked for upgrade (and some upgrades were already done), next to the area is mall with braided belts marked for upgrade ... which is destroying the braiding.

I tried to run the save in heavy mode for a while, also tried small-scale testing of underground belt upgrades (including of braided belts) with heavy mode turned on, but didn't managed to reproduce the desync.

So without more reports of the similar desyncs I won't be able to crack this one down.