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A buddy was messing around with trains and created a rail setup that causes the train to stutter forward (similar to this issue) until it eventually no-paths, stops, and then moves forward normally. It loops back around to the bottom station and repeats. This eventually caused a permanent desync on the server and nobody was able to log into the game. We were able to isolate the setup that caused the issue and recreate the desync in a brand new map with only a few rails and stations, which is the desync report I attached. If you would like the first desync report in our actual map, I can attach it as well. We thought it was odd that the train stuttering only happens on one particular station in the loop, when they are all set up identically.

Are you using mods or a custom scenario?

I used creative mod in single player to set up the map in the desync report, but loaded into a server with no mods or custom scenarios in order to create the desync

I couldn't reproduce the desync, but I have fixed the train stuttering.
Is it enough to just start a server, then connect to that server with one client and wait? How long does it take for you before it desyncs?

wheybags wrote:I couldn't reproduce the desync, but I have fixed the train stuttering.
Is it enough to just start a server, then connect to that server with one client and wait? How long does it take for you before it desyncs?

I tried to reproduce the desync my self the other day when this was first reported and couldn't. I ran the save for 5 minutes in heavy mode and it had no problems.

On the demo map in desync report my buddy triggered the desync by running in front of the train after it hit the no path and resumed, while I stood watching. From my POV he didn't move, just desynced and got booted offline. I did not desync and stayed in game. I'll see if I can reproduce again.

Well we spent about 30 minutes trying to recreate it and failed, both on the demo map and our actual save. I can provide the original desync report on the large map, but it is too large to attach. Do you need it?

I think it's fine, let us know if you can reproduce it again in 0.16.24 once it's released.
Thanks for the report!