[Qgis-user] QGIS server: raster layer turn white

[Thomas Schüttenberg]

Hi there!

I'm trying to serve a raster terrain model as a wms with QGIS server 3.4. The layer is a virtual raster consiting of geotiffs with external pyramids and the server has access to all files. 
As well as in QGIS desktop the wms it is correctly displayed when served (QGIS as client), but only at relatively small scales (in this case > ~1:12800). When zooming in, the wms rasterlayer disapears, or better said, only a white picture is served. 

I have no clue why this happens, there are no errors in the logs. Has anyone experienced such behavior? 

Note: certainly there is no scale dependant visibility configured in the .qgs! ;-)

All the best
Thomas