Dear developers, I wrote a code that extracts subDMs corresponding to the various strata in the Face Sets. I run into troubles when I view a subDM or a Vec attached to the subDM using the VTK format. More precisely, the problem only occurs on more than one processor when the rank=0 processor has no points on a given subDM. For instance, when the attached reproducer is run on 2 procs, the u_01.vtu file (global u Vec mapped to the subDM corresponding to stratum=1) only includes the header, but no data. All other u_0?.vtu files can successfully be loaded and viewed in paraview. The problem does NOT arise when I view the same objects in HDF5 format. However, my problem in using the HDF5 lies in the fact that: while the hdf5 file obtained with DMView can be post-processed with "petsc/lib/petsc/bin/petsc_gen_xdmf.py" to create a xmf file readable by paraview I do not know how to view the field(s) associated with the DM when the hdf5 file is obtained from VecView. The reproducer compiles with the latest petsc release. Thanks, Aldo -- Dr. Aldo Bonfiglioli Associate professor of Fluid Mechanics Dipartimento di Ingegneria Universita' della Basilicata V.le dell'Ateneo Lucano, 10 85100 Potenza ITALY tel:+39.0971.205203 fax:+39.0971.205215 web: https://urldefense.us/v3/__http://docenti.unibas.it/site/home/docente.html?m...