We are having some intermittent faults with GeoServer at the moment. We have a mapping application - http://explorer.geowessex.com - that makes WMS requests to our Geoserver to retrieve tiles. The layers are properly loaded and work via GeoServers built in 'Layer Preview' function, but sometimes in the application the tiles don't load. In the Firebug Net Panel you will see all the WMS Get Requests being fired when a layer is loaded and they say they return with no errors. In reality if you open one of these response in a new tab you get the following XML file.
<?xml version="1.0" encoding="UTF-8" standalone="no"?><!DOCTYPE ServiceExceptionReport SYSTEM "http://wms.geowessex.com:80/geoserver/schemas/wms/1.1.1/WMS_exception_1_1_1.dtd"> <ServiceExceptionReport version="1.1.1" ><ServiceException code="LayerNotDefined"> Could not find layer 'workspacename':'layername'
Which is stupid because it definitely exists, I can see it load perfectly well in GeoServer layer preview. What's even more annoying is that sometimes it doesn't even return this, it just gives the error '400:Problem communicating with GeoServer'. On top of that I cannot reproduce it regularly, I can have the map up, turn on a layer and it wont work. Turn on another layer and it will, go back and turn the other layer back on and it will start working again.
I'm really banging my head against a brick wall here. GeoServers own documentation is not that good for troubleshooting and I must've done enough Google searches to bring down their servers in the last two days and am still no closer as to why this happens.
Anyone experienced this themselves? Suggestions, comments anything is hugely welcome, and if you need any more info let me know.