fix and closes idaholab#15793

framework/src/meshgenerators/BreakMeshByBlockGenerator.C

@@ -221,6 +221,7 @@ BreakMeshByBlockGenerator::generate()
   }     // end nodeptr check
 
   addInterfaceBoundary(*mesh);
+  Partitioner::set_node_processor_ids(*mesh);
   return dynamic_pointer_cast<MeshBase>(mesh);
 }
 

test/tests/meshgenerators/break_mesh_by_block_generator/hanging_nodes_parallel.i

@@ -0,0 +1,83 @@
+[Mesh]
+  [./msh]
+    type = GeneratedMeshGenerator
+    nx = 2
+    ny = 3
+    nz = 4
+    xmin = -2.5
+    xmax = 2.5
+    ymin = -2
+    ymax = 2
+    zmin = -1.5
+    zmax = 1.5
+    dim = 3
+  [../]
+  [Partitioner]
+    type = GridPartitioner
+    nx = 1
+    ny = 3
+    nz = 4
+  []
+  [./subdomain_1]
+    type = SubdomainBoundingBoxGenerator
+    input = msh
+    bottom_left = '-2.5 -2 -1'
+    top_right = '2.5 0 0.5'
+    block_id = 1
+  []
+  [./subdomain_2]
+    type = SubdomainBoundingBoxGenerator
+    input = subdomain_1
+    bottom_left = '-2.5 0 -1'
+    top_right = '2.5 2 0.5'
+    block_id = 2
+  []
+  [./subdomain_3]
+    type = SubdomainBoundingBoxGenerator
+    input = subdomain_2
+    bottom_left = '-2.5 -2 0.5'
+    top_right = '1.25 2 1.5'
+    block_id = 3
+  []
+  [./subdomain_4]
+    type = SubdomainBoundingBoxGenerator
+    input = subdomain_3
+    bottom_left = '1.25 -2 0.5'
+    top_right = '5 2 1.5'
+    block_id = 4
+  []
+  [./subdomain_5]
+    type = SubdomainBoundingBoxGenerator
+    input = subdomain_4
+    bottom_left = '-2.5 -2 -1.5'
+    top_right = '1.25 2 -1'
+    block_id = 3
+  []
+  [./subdomain_6]
+    type = SubdomainBoundingBoxGenerator
+    input = subdomain_5
+    bottom_left = '1.25 -2 -1.5'
+    top_right = '2.5 2 -1'
+    block_id = 4
+  []
+  [./split]
+    type = BreakMeshByBlockGenerator
+    input = subdomain_6
+  []
+[]
+
+[Debug]
+  pid_aux = true
+[]
+
+[Problem]
+  solve = false
+[]
+
+[Executioner]
+  type = Steady
+[]
+
+[Outputs]
+  exodus = true
+[]

test/tests/meshgenerators/break_mesh_by_block_generator/tests

@@ -149,4 +149,17 @@
                'interface;'
     []
   []
+
+  [hanging_nodes]
+    type = 'Exodiff'
+    input = 'hanging_nodes_parallel.i'
+    exodiff = 'hanging_nodes_parallel_out.e'
+    requirement = 'The system shall properly assign node processor ids for paritioned meshes'
+    design = 'meshgenerators/BreakMeshByBlockGenerator.md'
+    issues = '#15793'
+    mesh_mode = 'REPLICATED'
+    min_parallel = 12
+    max_parallel = 12
+    recover = false
+  []
 []