Flowable unable to start process Instances

Flowable is throwing error
Connection refused: connect

I checked over internet, found out flowable was trying making an internet connection but unable to do that while I am running another springboot application which is running fine
I don’t know what the error is actually

2018-11-22 18:03:11.502 ERROR 1828 — [nio-3000-exec-1] o.a.c.c.C.[.[.[/].[dispatcherServlet] : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.flowable.common.engine.api.FlowableException: IO exception occurred] with root cause

java.net.ConnectException: Connection refused: connect
at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method) ~[na:1.8.0_171]
at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:85) ~[na:1.8.0_171]
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350) ~[na:1.8.0_171]
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206) ~[na:1.8.0_171]
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188) ~[na:1.8.0_171]
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172) ~[na:1.8.0_171]
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) ~[na:1.8.0_171]
at java.net.Socket.connect(Socket.java:589) ~[na:1.8.0_171]
at org.apache.http.conn.socket.PlainConnectionSocketFactory.connectSocket(PlainConnectionSocketFactory.java:75) ~[httpclient-4.5.6.jar:4.5.6]
at org.apache.http.impl.conn.DefaultHttpClientConnectionOperator.connect(DefaultHttpClientConnectionOperator.java:142) ~[httpclient-4.5.6.jar:4.5.6]
at org.apache.http.impl.conn.PoolingHttpClientConnectionManager.connect(PoolingHttpClientConnectionManager.java:373) ~[httpclient-4.5.6.jar:4.5.6]
at org.apache.http.impl.execchain.MainClientExec.establishRoute(MainClientExec.java:394) ~[httpclient-4.5.6.jar:4.5.6]
at org.apache.http.impl.execchain.MainClientExec.execute(MainClientExec.java:237) ~[httpclient-4.5.6.jar:4.5.6]
at org.apache.http.impl.execchain.ProtocolExec.execute(ProtocolExec.java:185) ~[httpclient-4.5.6.jar:4.5.6]
at org.apache.http.impl.execchain.RetryExec.execute(RetryExec.java:89) ~[httpclient-4.5.6.jar:4.5.6]
at org.apache.http.impl.execchain.RedirectExec.execute(RedirectExec.java:110) ~[httpclient-4.5.6.jar:4.5.6]
at org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:185) ~[httpclient-4.5.6.jar:4.5.6]
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:83) ~[httpclient-4.5.6.jar:4.5.6]
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:108) ~[httpclient-4.5.6.jar:4.5.6]
at org.flowable.http.HttpActivityExecutor.perform(HttpActivityExecutor.java:254) ~[flowable-http-6.3.1.jar:6.3.1]
at org.flowable.http.HttpActivityExecutor.execute(HttpActivityExecutor.java:88) ~[flowable-http-6.3.1.jar:6.3.1]
at org.flowable.http.bpmn.impl.HttpActivityBehaviorImpl.execute(HttpActivityBehaviorImpl.java:202) ~[flowable-http-6.3.1.jar:6.3.1]
at org.flowable.engine.impl.agenda.ContinueProcessOperation.executeActivityBehavior(ContinueProcessOperation.java:258) ~[flowable-engine-6.3.1.jar:6.3.1]
at org.flowable.engine.impl.agenda.ContinueProcessOperation.executeSynchronous(ContinueProcessOperation.java:155) ~[flowable-engine-6.3.1.jar:6.3.1]
at org.flowable.engine.impl.agenda.ContinueProcessOperation.continueThroughFlowNode(ContinueProcessOperation.java:112) ~[flowable-engine-6.3.1.jar:6.3.1]
at org.flowable.engine.impl.agenda.ContinueProcessOperation.continueThroughSequenceFlow(ContinueProcessOperation.java:305) ~[flowable-engine-6.3.1.jar:6.3.1]
at org.flowable.engine.impl.agenda.ContinueProcessOperation.run(ContinueProcessOperation.java:78) ~[flowable-engine-6.3.1.jar:6.3.1]
at org.flowable.engine.impl.interceptor.CommandInvoker.executeOperation(CommandInvoker.java:88) ~[flowable-engine-6.3.1.jar:6.3.1]
at org.flowable.engine.impl.interceptor.CommandInvoker.executeOperations(CommandInvoker.java:72) ~[flowable-engine-6.3.1.jar:6.3.1]
at org.flowable.engine.impl.interceptor.CommandInvoker.execute(CommandInvoker.java:56) ~[flowable-engine-6.3.1.jar:6.3.1]
at org.flowable.engine.impl.interceptor.BpmnOverrideContextInterceptor.execute(BpmnOverrideContextInterceptor.java:25) ~[flowable-engine-6.3.1.jar:6.3.1]
at org.flowable.common.engine.impl.interceptor.TransactionContextInterceptor.execute(TransactionContextInterceptor.java:53) ~[flowable-engine-common-6.3.1.jar:6.3.1]
at org.flowable.common.engine.impl.interceptor.CommandContextInterceptor.execute(CommandContextInterceptor.java:71) ~[flowable-engine-common-6.3.1.jar:6.3.1]
at org.flowable.idm.spring.SpringTransactionInterceptor$1.doInTransaction(SpringTransactionInterceptor.java:49) ~[flowable-idm-spring-6.3.1.jar:6.3.1]
at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:140) ~[spring-tx-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.flowable.idm.spring.SpringTransactionInterceptor.execute(SpringTransactionInterceptor.java:46) ~[flowable-idm-spring-6.3.1.jar:6.3.1]
at org.flowable.common.engine.impl.interceptor.LogInterceptor.execute(LogInterceptor.java:30) ~[flowable-engine-common-6.3.1.jar:6.3.1]
at org.flowable.common.engine.impl.cfg.CommandExecutorImpl.execute(CommandExecutorImpl.java:56) ~[flowable-engine-common-6.3.1.jar:6.3.1]
at org.flowable.common.engine.impl.cfg.CommandExecutorImpl.execute(CommandExecutorImpl.java:51) ~[flowable-engine-common-6.3.1.jar:6.3.1]
at org.flowable.engine.impl.RuntimeServiceImpl.startProcessInstanceByKey(RuntimeServiceImpl.java:95) ~[flowable-engine-6.3.1.jar:6.3.1]
at org.flowable.demo.service.MyService.startProcess(MyService.java:61) ~[classes/:na]
at org.flowable.demo.controller.MyController.startProcess(MyController.java:22) ~[classes/:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_171]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_171]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_171]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_171]
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:209) ~[spring-web-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136) ~[spring-web-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102) ~[spring-webmvc-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:891) ~[spring-webmvc-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:797) ~[spring-webmvc-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991) ~[spring-webmvc-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925) ~[spring-webmvc-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:974) ~[spring-webmvc-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:866) ~[spring-webmvc-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:635) ~[tomcat-embed-core-8.5.34.jar:8.5.34]
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:851) ~[spring-webmvc-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) ~[tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat-embed-websocket-8.5.34.jar:8.5.34]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.34.jar:8.5.34]
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.34.jar:8.5.34]
at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:109) ~[spring-web-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.34.jar:8.5.34]
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93) ~[spring-web-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.34.jar:8.5.34]
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200) ~[spring-web-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) ~[tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:493) [tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) [tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) [tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:800) [tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:806) [tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1498) [tomcat-embed-core-8.5.34.jar:8.5.34]
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.34.jar:8.5.34]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_171]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_171]
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.34.jar:8.5.34]
at java.lang.Thread.run(Thread.java:748) [na:1.8.0_171]

Looking at the stacktrace I see that the error occurs in the HTTP Task. Which means that the tasks is misconfigured or the service that the task tries to access is down.