Just discovered that I'm not able to pull in a cached service as WMS while the cache format is compact. As exploded, it works great. Anyone experienced anything like this? For reference, I did very recently upgrade from 10.2.2 to 10.3. But this service is newly deployed, post-upgrade.
I get the very ambiguous 'There is an error during the draw (1.) Unspecified error' log entry.
OK, so it looks like it fails when the request comes in as EPSG:3857. Works in EPSG:4326. Tested in Postman.
So, to clarify:
Service with Compact Cache as WMS:
Fails in EPSG:3857, don't know about other projections. Succeeds in EPSG:4326
Service with Exploded Cache as WMS:
Succeeds regardless of projection.