Restart Files

For a coupled analysis run in one of System Coupling's user interfaces, results are written to a System Coupling Restart file at the end of the last coupling step or iteration completed. By default, these files are written to the SyC subdirectory in System Coupling's working directory.

Restart files are named according to the convention Restart_step<#>.h5 or Restart_iter<#>.h5, where "#" is the index of the corresponding coupling step or iteration.

Note:  Restart files named according to previous conventions (that is, Results_step<#>|iter<#>.h5 or Results_<#>.h5) are still supported. System Coupling can read these files but names all new files according to the new conventions.

By default, when a restart point is created by any method, a Restart file containing the information necessary to restart the coupled analysis at the end of the last completed step or iteration is written to the SyC subdirectory in System Coupling's working directory.

When a coupled analysis stops, either because it completed or was shut down, a listing of the Restart files created is written to the Available Restart Points table at the end of the Transcript\Log file.

Restart files may correspond either to coupling iterations or coupling steps, depending on the analysis type and whether the participants involved support the creation of restart points for iterations, as follows:

Step-based restart files:

  • Produced for:

    • Transient analyses

    • Steady-state analyses that include a participant that can only create restart points per step (that is, which have a ParticipantType of AEDT, CFX, MAPDL, or EXTERNALDATA)

  • Named according to the convention Restart_step<#>.h5, where "#" is the index of the coupling step

Iteration-based restart files:

  • Produced for:

    • Steady-state analyses that include only participants that can create restart points per iteration (that is, which do not have a ParticipantType of AEDT, CFX, MAPDL, or EXTERNALDATA)

  • Named according to the convention Restart_iter<#>.h5, where "#" is the index of the coupling iteration

When you restart an analysis, by default the Restart file associated with the last solved coupling step or iteration is used. If you want to begin from an earlier restart point, then you can use the following methods to specify the restart point to be used:

  • From the CLI, run the Open() command with the CouplingStep or CouplingIteration argument.

  • From the GUI, use the File > Open at step or File > Open at iteration options.

Note, however, that when restarting from an earlier point, all the later restart points stored in the same directory are removed (that is, the Restart files are deleted). To keep restart data for one of these later coupling steps or iterations, save the analysis state to a snapshot before starting participants. For more information, see Working with Coupled Analysis Snapshots.

For more detailed information on restart points and how to use them in one of System Coupling's user interfaces, see Restarting a Coupled Analysis.