On GeoServer I have two layers, both cascading a remote WMS. Both layers work fine in the layer preview.
Now I am putting both into one group layer and open the preview, which shows an empty response. When trying to query the group layer in the browser with
I get the following response:
Rendering process failed Argument "bgColor" should not be null.
When I add
&bgColor=0xFFFFFF to the request, I still get the same error response.
The same happens, when I call the underlying layers within the
layers parameter, without using the group layer.
I thought, it might be about different WMS implementations on the remote WMS side, but even when I switch to different remote WMS services, the problem persists.
When Googling, I didn't find a response that seems to solve the problem. Do I miss something?
The WMS services I am using are
- http://www.geodaten-mv.de/dienste/adv_dop, layer mv_dop
- https://geodienste.sachsen.de/wms_geosn_dop-rgb/guest, layer sn_dop_020