The resource did not process correctly

com.mongodb.MongoTimeoutException: Timed out after 30000 ms while waiting for a server that matches ReadPreferenceServerSelector{readPreference=primary}. Client view of cluster state is {type=UNKNOWN, servers=[{address=101.201.198.67:27017, type=UNKNOWN, state=CONNECTING, exception={com.mongodb.MongoSocketOpenException: Exception opening socket}, caused by {java.net.ConnectException: Connection refused: connect}}]
	at com.mongodb.connection.BaseCluster.createTimeoutException(BaseCluster.java:370)
	at com.mongodb.connection.BaseCluster.selectServer(BaseCluster.java:101)
	at com.mongodb.binding.ClusterBinding$ClusterBindingConnectionSource.(ClusterBinding.java:75)
	at com.mongodb.binding.ClusterBinding$ClusterBindingConnectionSource.(ClusterBinding.java:71)
	at com.mongodb.binding.ClusterBinding.getReadConnectionSource(ClusterBinding.java:63)
	at com.mongodb.operation.OperationHelper.withConnection(OperationHelper.java:166)
	at com.mongodb.operation.FindOperation.execute(FindOperation.java:394)
	at com.mongodb.operation.FindOperation.execute(FindOperation.java:57)
	at com.mongodb.Mongo.execute(Mongo.java:738)
	at com.mongodb.Mongo$2.execute(Mongo.java:725)
	at com.mongodb.DBCollection.findOne(DBCollection.java:737)
	at com.mongodb.DBCollection.findOne(DBCollection.java:710)
	at com.mongodb.DBCollection.findOne(DBCollection.java:657)
	at com.deepdv.web.CommonDAO.loadByOneField(CommonDAO.java:147)
	at com.deepdv.web.DbUtil.getSiteCode(DbUtil.java:36)
	at com.deepdv.web.InfoServlet.doGet(InfoServlet.java:75)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:634)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at com.deepdv.web.CommonFilter.doFilter(CommonFilter.java:161)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
	at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:690)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:373)
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1590)
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:748)