Sometimes it can be convenient to restart a simulation after a crash or to restricted queue limits on a cluster. Imagine your code ran and the output file output_3.vtu was succesfully writen. By adding a new tag Restart to the intital configuration file and specifying the path to the last output file using the tag File. Note that you have to be careful with the Step, since this the step is 3*500=1500 and not 3. Note that 3 is the third output file which corespond to the 1500 step, since the output interval is 500. Your simulation is started from the step 1500 and all the restart values are loaded from the file File: out/output_3.vtu.

Output:
 Path: out/
 Output_Interval: 500
Restart:
  File: out/output_3.vtu
  Step: 1500

The complete YAML configuration file is available here.