render farm Pre-Flight Error: Unable to import previously rendered file.
by Adam Katz on May 4, 2011 at 5:07:23 pm
I have an error message I am receiving during network rendering on a renderfarm, and was hoping for some help. The error is this: "Pre-Flight Error: Unable to import previously rendered file."
Here is my setup and some details:
The user makes a comp, and adds it to the render queue set to render as a quicktime movie file. Then they run a script which precomps everything and sets it to render as a image sequence with "Skip existing files" checked. This comp also has a post-render action set to import & replace usage. After this comp is rendered, it gets pulled back into the project and the original render item starts rendering the movie file using the previously rendered image sequence as it's only layer.
This project gets saved to a server where our render nodes are watching the folder. All the render nodes pick up the project and proceed to render the image sequence. Then, after they are done, 1 machine will pick up the second render item and begin rendering the image sequence into the final quicktime movie.
All of this goes smoothly about 90% of the time. However, in some cases an error shows up in the watch folder html page for the 2nd render item (the one converting the image sequence to the movie). The error says "Pre-Flight Error: Unable to import previously rendered file." After the error occurs, no machines will start rendering the project.
My first guess is that the render engine on one machine somehow skips rendering the image sequence comp, and then tries to render the quicktime movie comp and fails because the image sequence has not yet been rendered. However, I can't figure out why After Effects would skip rendering the first comp.
Does anyone have any idea?
Thanks for the help, and let me know if you have any more questions about the setup,