I note that entering "/15 * * * *" in the 'Poll SCM' job config field causes a crash:
Exception: java.lang.RuntimeException: Failed to instantiate class hudson.triggers.SCMTrigger from {"scmpoll_spec":"/15 * * * *"} Stacktrace: javax.servlet.ServletException: java.lang.RuntimeException: Failed to instantiate class hudson.triggers.SCMTrigger from {"scmpoll_spec":"/15 * * * *"} at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:616) at org.kohsuke.stapler.Stapler.invoke(Stapler.java:659) at org.kohsuke.stapler.MetaClass$6.doDispatch(MetaClass.java:241) at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:53) at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:574) at org.kohsuke.stapler.Stapler.invoke(Stapler.java:659) at org.kohsuke.stapler.MetaClass$6.doDispatch(MetaClass.java:241) at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:53) at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:574) at org.kohsuke.stapler.Stapler.invoke(Stapler.java:659) at org.kohsuke.stapler.Stapler.invoke(Stapler.java:488) at org.kohsuke.stapler.Stapler.service(Stapler.java:162) at javax.servlet.http.HttpServlet.service(HttpServlet.java:722) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:95) at hudson.plugins.audit_trail.AuditTrailFilter.doFilter(AuditTrailFilter.java:66) at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:98) at hudson.plugins.greenballs.GreenBallFilter.doFilter(GreenBallFilter.java:58) at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:98) at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:87) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:47) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.jenkinsci.plugins.reverse_proxy_auth.ReverseProxySecurityRealm$1.doFilter(ReverseProxySecurityRealm.java:92) at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:164) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.kohsuke.stapler.compression.CompressionFilter.doFilter(CompressionFilter.java:50) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at hudson.util.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:81) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407) at org.apache.coyote.ajp.AjpProcessor.process(AjpProcessor.java:200) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:585) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603) at java.lang.Thread.run(Thread.java:679) Caused by: java.lang.RuntimeException: Failed to instantiate class hudson.triggers.SCMTrigger from {"scmpoll_spec":"/15 * * * *"} at hudson.model.Descriptor.newInstance(Descriptor.java:575) at hudson.model.AbstractProject.buildDescribable(AbstractProject.java:1867) at hudson.model.AbstractProject.submit(AbstractProject.java:1846) at hudson.model.Project.submit(Project.java:197) at hudson.model.Job.doConfigSubmit(Job.java:1001) at hudson.model.AbstractProject.doConfigSubmit(AbstractProject.java:706) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:616) at org.kohsuke.stapler.Function$InstanceFunction.invoke(Function.java:288) at org.kohsuke.stapler.Function.bindAndInvoke(Function.java:151) at org.kohsuke.stapler.Function.bindAndInvokeAndServeResponse(Function.java:90) at org.kohsuke.stapler.MetaClass$1.doDispatch(MetaClass.java:111) at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:53) at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:574) ... 49 more Caused by: java.lang.IllegalArgumentException: Failed to instantiate class hudson.triggers.SCMTrigger from {"scmpoll_spec":"/15 * * * *"} at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:633) at org.kohsuke.stapler.RequestImpl.bindJSON(RequestImpl.java:377) at org.kohsuke.stapler.RequestImpl.bindJSON(RequestImpl.java:373) at hudson.model.Descriptor.newInstance(Descriptor.java:566) ... 64 more Caused by: java.lang.IllegalArgumentException: antlr.ANTLRException: Invalid input: "/15 * * * *": line 1:1: unexpected token: / at org.kohsuke.stapler.RequestImpl.invokeConstructor(RequestImpl.java:439) at org.kohsuke.stapler.RequestImpl.access$300(RequestImpl.java:76) at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:631) ... 67 more Caused by: antlr.ANTLRException: Invalid input: "/15 * * * *": line 1:1: unexpected token: / at hudson.scheduler.CronTabList.create(CronTabList.java:87) at hudson.scheduler.CronTabList.create(CronTabList.java:73) at hudson.triggers.Trigger.<init>(Trigger.java:161) at hudson.triggers.SCMTrigger.<init>(SCMTrigger.java:78) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:532) at org.kohsuke.stapler.RequestImpl.invokeConstructor(RequestImpl.java:424) ... 69 more Caused by: line 1:1: unexpected token: / at hudson.scheduler.CrontabParser.startRule(CrontabParser.java:166) at hudson.scheduler.CronTab.set(CronTab.java:90) at hudson.scheduler.CronTab.<init>(CronTab.java:80) at hudson.scheduler.CronTabList.create(CronTabList.java:85) ... 77 more <phew> Well, I should of course have typed "*/5 * * * *" but it seems a bit off that this simple data entry error should bring Jenkins tumblin' down like a big ol' tower o' cards.