I'm using KnowledgeAgent to poll regularly for three DRL files hosted on a web server. If the web server goes down for any reason or one of the DRL files becomes unavailable, the change scanner and knowledge agent unsubscribe from the resource(s) that were unavailable. After reading some topics on the forum, I found that setting the drools.resource.urlcache system property should correct this. However, I've been unable to get this to work properly. The code I'm using is below. Any insight into what I'm doing wrong would be appreciated. I'm using drools 5.1.1. System.setProperty("drools.dateformat", "MM/dd/yyyy"); System.setProperty("drools.resource.urlcache", "C:\\Users\\0000000\\Documents\\rule-cache"); //start the scanner service and resource change notifier service changeNotifier = ResourceFactory.getResourceChangeNotifierService(); changeScanner = ResourceFactory.getResourceChangeScannerService(); changeNotifier.start(); changeScanner.start(); kagent = KnowledgeAgentFactory.newKnowledgeAgent("My Knowledge Agent"); URL url = RulesRuntimeImpl.class.getResource(CHANGE_SET_PATH); Resource drl = ResourceFactory.newUrlResource(url); kagent.applyChangeSet(drl); My change set file looks like this: <change-set xmlns="http://drools.org/drools-5.0/change-set" xmlns:xs="http://www.w3.org/2001/XMLSchema-instance" xs:schemaLocation="http://drools.org/drools-5.0/change-set drools-change-set-5.0.xsd" > <add> <resource source="http://mysite.com/test/FirstDecisionTable.drl" type="DRL" /> <resource source="http://mysite.com/test/SecondDecisionTable.drl" type="DRL" /> <resource source="http://mysite.com/test/ThirdDecisionTable.drl" type="DRL" /> </add> </change-set> and the output I get when a resource in the change set becomes unavailable: [9/21/11 10:49:28:015 EDT] 0000004e SystemOut O [2011:09:264 10:09:15:debug] ResourceChangeScanner attempt to scan 3 resources [9/21/11 10:49:28:046 EDT] 0000004e SystemOut O [2011:09:264 10:09:46:debug] ResourceChangeScanner thread is waiting for 60 seconds. [9/21/11 10:50:28:055 EDT] 0000004e SystemOut O [2011:09:264 10:09:55:debug] ResourceChangeScanner attempt to scan 3 resources [9/21/11 10:50:28:259 EDT] 0000004e SystemOut O [2011:09:264 10:09:259:debug] ResourceChangeScanner removed resource=[UrlResource path='http://mysite.com/test/FirstDecisionTable.drl'] [9/21/11 10:50:28:309 EDT] 0000004e SystemOut O [2011:09:264 10:09:309:debug] ResourceChangeNotification received ChangeSet notification [9/21/11 10:50:28:345 EDT] 0000004e SystemOut O [2011:09:264 10:09:345:debug] ResourceChangeScanner thread is waiting for 60 seconds. [9/21/11 10:50:28:426 EDT] 0000004f SystemOut O [2011:09:264 10:09:417:debug] ResourceChangeNotification processing ChangeSet [9/21/11 10:50:28:535 EDT] 0000004f SystemOut O [2011:09:264 10:09:535:debug] ResourceChangeNotification ChangeSet removed resource=[UrlResource path='http://mysite.com/test/FirstDecisionTable.drl'] for listener=org.drools.agent.impl.KnowledgeAgentImpl@6e5a6e5a [9/21/11 10:50:28:560 EDT] 0000004f SystemOut O [2011:09:264 10:09:560:debug] KnowledgeAgent received ChangeSet changed notification [9/21/11 10:50:28:611 EDT] 0000004f SystemOut O [2011:09:264 10:09:611:debug] ResourceChangeNotification thread is waiting for queue update [9/21/11 10:50:28:626 EDT] 00000050 SystemOut O [2011:09:264 10:09:625:info] KnowledgeAgent applying ChangeSet [9/21/11 10:50:28:663 EDT] 00000050 SystemOut O [2011:09:264 10:09:663:debug] KnowledgeAgent removing mappings for resource=[UrlResource path='http://mysite.com/test/FirstDecisionTable.drl'] with unsubscribe=true [9/21/11 10:50:28:684 EDT] 00000050 SystemOut O [2011:09:264 10:09:684:debug] KnowledgeAgent notifier unsubscribing to resource=[UrlResource path='http://mysite.com/test/FirstDecisionTable.drl'] [9/21/11 10:50:28:689 EDT] 00000050 SystemOut O [2011:09:264 10:09:689:debug] ResourceChangeNotification unsubscribing listener=org.drools.agent.impl.KnowledgeAgentImpl@6e5a6e5a to resource=[UrlResource path='http://mysite.com/test/FirstDecisionTable.drl'] [9/21/11 10:50:28:689 EDT] 00000050 SystemOut O [2011:09:264 10:09:689:debug] KnowledgeAgent rebuilding KnowledgeBase using ChangeSet ... -- View this message in context: http://drools.46999.n3.nabble.com/Help-with-URL-resource-caching-tp336204... Sent from the Drools: User forum mailing list archive at Nabble.com.