Fix: Docker Stop Not Saving Factorio - Large Save Files

Are you experiencing issues with Docker failing to properly save your Factorio game progress when you use the docker stop command? This can be incredibly frustrating, especially with large save files. You're not alone! Many Factorio players using Docker have encountered this problem. This article delves into the common causes and provides effective solutions to ensure your progress is saved correctly.

Understanding the Problem: Why Factorio Saves May Fail with Docker Stop

When you issue a docker stop command, Docker sends a SIGTERM signal to the main process within the container, in this case, the Factorio server. This signal politely asks the application to shut down. Factorio, upon receiving this signal, initiates the save process. However, the problem arises when the save process takes longer than the default timeout Docker allows before forcefully terminating the container with a SIGKILL signal. This abrupt termination can interrupt the save process, leading to corrupted or incomplete save files.

With large Factorio save files, the save operation can be quite lengthy, especially on systems with slower storage or higher server loads. The default Docker timeout, which is typically 10 seconds, is often insufficient for these larger saves to complete. Even when you attempt to increase the timeout using docker stop -t 120 factorio, the issue might persist if the timeout isn't correctly applied or if the save process takes even longer than the specified timeout.

Another contributing factor can be the way Factorio handles temporary files during the save process. The creation of temporary files, like the MainServer.tmp.zip you mentioned, is a normal part of the save procedure. However, if the container is killed prematurely, these temporary files might not be properly finalized and could result in incomplete saves. Therefore, understanding these processes is the first step toward solving the problem.

Diagnosing the Issue: Key Indicators

To effectively troubleshoot, it's essential to identify the telltale signs of this problem. Here's what to look for:

• Incomplete Save Files: The most obvious sign is the presence of incomplete or corrupted save files in your Factorio saves directory. This could manifest as missing progress, rollbacks to previous states, or even the inability to load the save file altogether.
• Temporary Files: The existence of .tmp files, like MainServer.tmp.zip, in your saves folder after a docker stop command is a strong indicator that the save process was interrupted.
• Docker Logs: Examining the Docker logs for your Factorio container is crucial. Look for messages related to the SIGTERM signal, the start of the save process, and any potential errors or warnings that might appear before the container is killed. The logs you provided in the original problem description are a great example of this, showing the