Portal for ArcGIS 10.3.1 fails to render route polyline from certain network dataset route services, despite valid geometry, stops, and polyline features being returned by the service. This issue occurs because the geometry is decompressed as nulls in the 'itemID' file when the Z values are present in this response.

Additional Information

Workaround

Rebuild the Roads feature class and use a network dataset without Z values.

1. Relationship class feature dataset > New feature class > ‘Roads_noZ’. Enable M values on this feature class but disable Z values.
2. Search for the Append (Data Management) tool and append all the records from Roads to Roads_noZ. A message displays, advising that Z values are not carried over due to no corresponding field.
3. Relationship class feature dataset > New > Network Dataset.
4. Build this network dataset with the same parameters as before and on one of the New Network Dataset dialog boxes, when prompted with a message, 'How would you like to model the elevation of your network features,' click NONE.
5. Publish this new network dataset from a route and confirm the directions are found with Portal for ArcGIS 10.3.1 and check the rendered route directions.

Steps to Reproduce