Yesterday I tackled this extremely annoying bug, which kept me annoyed for about 10 hours in a row. We are using a GIS software called ArcGIS Server, which one of its main uses is to supply maps – In our case, images passed to a web-control which comes with the software. Everything worked nice and dandy until we installed our new version on a new production server. The maps would not display and all we got to see is WHITE.
At the following hours I tried, among others, the following approaches:
- Recreating the cache for the maps (X 10 times)
- Moving the output directory around and playing with the permissions for it (X 5 times)
- Uninstalling and Reinstalling ArcGIS Server (X 1 time)
- Banging my head on the desk (X 20 times)
When all failed, I pointed my local machine to the server and moved into debug mode, stripping the map page into its most basic functionality, which still didn’t work. No errors appeared in the log. The images did seem to get created on the server, but for some reason I couldn’t see them in the client. Don’t know why it took me this long, but at about 23:00 o’clock it finally came to me to try using Fiddler in order to understand what’s going on in the network level. That’s when I saw this:
prodserver/ags_dfdjf.png: Sorry, unable to resolve DNS “prodserver”.
- Bang head on the desk (X 100 times)
Stupid, stupid, stupid. Should have pointed the virtual directory for the output images to prodserver.com. Why oh why didn’t I notice this sooner? To God the answers.
Bloody url extensions. Who needs them anyway.