You have to install the aws-java-sdk plugin.

can you make it so that the installation of the upgrade will pull in the dependency if it's not already there (user friendly)...see photo, it looks like the aws-sdk does this seamlessly.

This should already be done by Jenkins in the normal course of declaring a dependency on another plugin in the POM. https://wiki.jenkins-ci.org/display/JENKINS/Dependencies+among+plugins

I'm not sure why it's not working. Perhaps because the plugin was installed by uploading an hpi file directly and not through the normal means? Might be something to ask on the Jenkins list/IRC channel.

well in any rate the only time I can try this out is at off peak hours because this pipeline we created runs 24/7 and developers develop around the clock. I will try this later on this evening with the sdk plugin installed . more to come

1. I was able to install it. unfortunately i'm going ot have to roll back. Also the call that is being used to grab every instance id out of my vpc is costly because I have about 600+ running instances that are serving other purposes.

still mass failure. See log stack trace added

This happened after the demand had went to zero and jenkins was essentially idle for about 2 hours. A developer attempted to push a build which triggered the creation of a node and nothing happened on the gui.

stack trace 1.30-SNAPSHOT.hpi installed

Seems to be the same problem as the original. Need to have a core developer consider this.

Is the logging too much? I can reduce a lot of this logging to below INFO level. Beyond that, I'm not sure what you mean about the cost of grabbing every instance out of your VPC. It does have to look at all of the instances to determine if it can use an existing instance. But this should be relatively cheap (modulo the tracing).

Francis,

Yeah the INFO is a lot in the logs. But I wonder why that tempOfflineReason thing is coming back null?

still happening

*****
if this helps a ec2-plugin spunned up node was left in the ec2 console but was not attached to Jenkins. this causes some type of lock. And then the orphaned node stays there and jenkins refuses to attach ANY other nodes, not even ones attached manually. The below stacktrace with the evil jenkins is shown below
****

A problem occurred while processing the request. Please check our bug tracker to see if a similar problem has already been reported. If it is already reported, please vote and put a comment on it to let us gauge the impact of the problem. If you think this is a new issue, please file a new issue. When you file an issue, make sure to add the entire stack trace, along with the version of Jenkins and relevant plugins. The users list might be also useful in understanding what has happened.

Stack trace

javax.servlet.ServletException: java.lang.RuntimeException: Failed to serialize hudson.model.Node#temporaryOfflineCause for class hudson.slaves.DumbSlave
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:796)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:876)
at org.kohsuke.stapler.MetaClass$6.doDispatch(MetaClass.java:249)
at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:53)
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:746)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:876)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:649)
at org.kohsuke.stapler.Stapler.service(Stapler.java:238)
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:132)
at com.smartcodeltd.jenkinsci.plugin.assetbundler.filters.LessCSS.doFilter(LessCSS.java:47)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:129)
at hudson.plugins.audit_trail.AuditTrailFilter.doFilter(AuditTrailFilter.java:95)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:129)
at net.bull.javamelody.MonitoringFilter.doFilter(MonitoringFilter.java:200)
at net.bull.javamelody.MonitoringFilter.doFilter(MonitoringFilter.java:178)
at net.bull.javamelody.PluginMonitoringFilter.doFilter(PluginMonitoringFilter.java:85)
at org.jvnet.hudson.plugins.monitoring.HudsonMonitoringFilter.doFilter(HudsonMonitoringFilter.java:99)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:129)
at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:123)
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:49)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:84)
at hudson.security.UnwrapSecurityExceptionFilter.doFilter(UnwrapSecurityExceptionFilter.java:51)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at jenkins.security.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:117)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.providers.anonymous.AnonymousProcessingFilter.doFilter(AnonymousProcessingFilter.java:125)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.ui.rememberme.RememberMeProcessingFilter.doFilter(RememberMeProcessingFilter.java:142)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.ui.AbstractProcessingFilter.doFilter(AbstractProcessingFilter.java:271)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at jenkins.security.BasicHeaderProcessor.doFilter(BasicHeaderProcessor.java:93)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.context.HttpSessionContextIntegrationFilter.doFilter(HttpSessionContextIntegrationFilter.java:249)
at hudson.security.HttpSessionContextIntegrationFilter2.doFilter(HttpSessionContextIntegrationFilter2.java:67)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:76)
at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:171)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.kohsuke.stapler.compression.CompressionFilter.doFilter(CompressionFilter.java:49)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at hudson.util.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:81)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.kohsuke.stapler.DiagnosticThreadNameFilter.doFilter(DiagnosticThreadNameFilter.java:30)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:581)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
at org.apache.coyote.ajp.AjpProcessor.process(AjpProcessor.java:200)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:585)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.RuntimeException: Failed to serialize hudson.model.Node#temporaryOfflineCause for class hudson.slaves.DumbSlave
at hudson.util.RobustReflectionConverter$2.writeField(RobustReflectionConverter.java:215)
at hudson.util.RobustReflectionConverter$2.visit(RobustReflectionConverter.java:183)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:138)
at hudson.util.RobustReflectionConverter.doMarshal(RobustReflectionConverter.java:168)
at hudson.util.RobustReflectionConverter.marshal(RobustReflectionConverter.java:109)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:69)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:58)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:43)
at com.thoughtworks.xstream.core.TreeMarshaller.start(TreeMarshaller.java:82)
at com.thoughtworks.xstream.core.AbstractTreeMarshallingStrategy.marshal(AbstractTreeMarshallingStrategy.java:37)
at com.thoughtworks.xstream.XStream.marshal(XStream.java:1026)
at com.thoughtworks.xstream.XStream.marshal(XStream.java:1015)
at com.thoughtworks.xstream.XStream.toXML(XStream.java:988)
at hudson.XmlFile.write(XmlFile.java:178)
at jenkins.model.Nodes.save(Nodes.java:195)
at hudson.util.PersistedList.onModified(PersistedList.java:173)
at hudson.util.PersistedList.replaceBy(PersistedList.java:85)
at hudson.model.Slave.<init>(Slave.java:172)
at hudson.plugins.ec2.EC2AbstractSlave.<init>(EC2AbstractSlave.java:128)
at hudson.plugins.ec2.EC2OndemandSlave.<init>(EC2OndemandSlave.java:47)
at hudson.plugins.ec2.EC2OndemandSlave.<init>(EC2OndemandSlave.java:40)
at hudson.plugins.ec2.SlaveTemplate.newOndemandSlave(SlaveTemplate.java:838)
at hudson.plugins.ec2.SlaveTemplate.provisionOndemand(SlaveTemplate.java:568)
at hudson.plugins.ec2.SlaveTemplate.provision(SlaveTemplate.java:377)
at hudson.plugins.ec2.EC2Cloud.provisionSlaveIfPossible(EC2Cloud.java:406)
at hudson.plugins.ec2.EC2Cloud.doProvision(EC2Cloud.java:258)
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:606)
at org.kohsuke.stapler.Function$InstanceFunction.invoke(Function.java:298)
at org.kohsuke.stapler.Function.bindAndInvoke(Function.java:161)
at org.kohsuke.stapler.Function.bindAndInvokeAndServeResponse(Function.java:96)
at org.kohsuke.stapler.MetaClass$1.doDispatch(MetaClass.java:121)
at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:53)
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:746)
... 69 more
Caused by: java.lang.RuntimeException: Failed to serialize OfflineCause_groovyProxy#closureMap for class OfflineCause_groovyProxy
at hudson.util.RobustReflectionConverter$2.writeField(RobustReflectionConverter.java:215)
at hudson.util.RobustReflectionConverter$2.visit(RobustReflectionConverter.java:183)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:138)
at hudson.util.RobustReflectionConverter.doMarshal(RobustReflectionConverter.java:168)
at hudson.util.RobustReflectionConverter.marshal(RobustReflectionConverter.java:109)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:69)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller$1.convertAnother(AbstractReferenceMarshaller.java:84)
at hudson.util.RobustReflectionConverter.marshallField(RobustReflectionConverter.java:224)
at hudson.util.RobustReflectionConverter$2.writeField(RobustReflectionConverter.java:211)
... 104 more
Caused by: java.lang.RuntimeException: Failed to serialize groovy.lang.Closure#delegate for class Script1$_run_closure9
at hudson.util.RobustReflectionConverter$2.writeField(RobustReflectionConverter.java:215)
at hudson.util.RobustReflectionConverter$2.visit(RobustReflectionConverter.java:183)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:138)
at hudson.util.RobustReflectionConverter.doMarshal(RobustReflectionConverter.java:168)
at hudson.util.RobustReflectionConverter.marshal(RobustReflectionConverter.java:109)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:69)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:58)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:43)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller$1.convertAnother(AbstractReferenceMarshaller.java:88)
at com.thoughtworks.xstream.converters.collections.AbstractCollectionConverter.writeItem(AbstractCollectionConverter.java:64)
at com.thoughtworks.xstream.converters.collections.MapConverter.marshal(MapConverter.java:79)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:69)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller$1.convertAnother(AbstractReferenceMarshaller.java:84)
at hudson.util.RobustReflectionConverter.marshallField(RobustReflectionConverter.java:224)
at hudson.util.RobustReflectionConverter$2.writeField(RobustReflectionConverter.java:211)
... 113 more
Caused by: java.lang.RuntimeException: Failed to serialize groovy.lang.Script#binding for class Script1
at hudson.util.RobustReflectionConverter$2.writeField(RobustReflectionConverter.java:215)
at hudson.util.RobustReflectionConverter$2.visit(RobustReflectionConverter.java:183)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:138)
at hudson.util.RobustReflectionConverter.doMarshal(RobustReflectionConverter.java:168)
at hudson.util.RobustReflectionConverter.marshal(RobustReflectionConverter.java:109)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:69)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller$1.convertAnother(AbstractReferenceMarshaller.java:84)
at hudson.util.RobustReflectionConverter.marshallField(RobustReflectionConverter.java:224)
at hudson.util.RobustReflectionConverter$2.writeField(RobustReflectionConverter.java:211)
... 128 more
Caused by: java.lang.RuntimeException: Failed to serialize groovy.lang.Binding#variables for class groovy.lang.Binding
at hudson.util.RobustReflectionConverter$2.writeField(RobustReflectionConverter.java:215)
at hudson.util.RobustReflectionConverter$2.visit(RobustReflectionConverter.java:183)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:138)
at hudson.util.RobustReflectionConverter.doMarshal(RobustReflectionConverter.java:168)
at hudson.util.RobustReflectionConverter.marshal(RobustReflectionConverter.java:109)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:69)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller$1.convertAnother(AbstractReferenceMarshaller.java:84)
at hudson.util.RobustReflectionConverter.marshallField(RobustReflectionConverter.java:224)
at hudson.util.RobustReflectionConverter$2.writeField(RobustReflectionConverter.java:211)
... 137 more
Caused by: java.lang.RuntimeException: Failed to serialize hudson.Launcher#listener for class hudson.Launcher$LocalLauncher
at hudson.util.RobustReflectionConverter$2.writeField(RobustReflectionConverter.java:215)
at hudson.util.RobustReflectionConverter$2.visit(RobustReflectionConverter.java:183)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.visitSerializableFields(PureJavaReflectionProvider.java:138)
at hudson.util.RobustReflectionConverter.doMarshal(RobustReflectionConverter.java:168)
at hudson.util.RobustReflectionConverter.marshal(RobustReflectionConverter.java:109)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:69)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:58)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:43)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller$1.convertAnother(AbstractReferenceMarshaller.java:88)
at com.thoughtworks.xstream.converters.collections.AbstractCollectionConverter.writeItem(AbstractCollectionConverter.java:64)
at com.thoughtworks.xstream.converters.collections.MapConverter.marshal(MapConverter.java:79)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:69)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller$1.convertAnother(AbstractReferenceMarshaller.java:84)
at hudson.util.RobustReflectionConverter.marshallField(RobustReflectionConverter.java:224)
at hudson.util.RobustReflectionConverter$2.writeField(RobustReflectionConverter.java:211)
... 146 more
Caused by: com.thoughtworks.xstream.converters.ConversionException: Could not call hudson.model.StreamBuildListener.writeObject() : Could not call hudson.remoting.RemoteOutputStream.writeObject() : null
---- Debugging information ----
message : Could not call hudson.remoting.RemoteOutputStream.writeObject()
cause-exception : java.lang.NullPointerException
cause-message : null
-------------------------------
message : Could not call hudson.model.StreamBuildListener.writeObject()
cause-exception : com.thoughtworks.xstream.converters.ConversionException
cause-message : Could not call hudson.remoting.RemoteOutputStream.writeObject() : null
-------------------------------
at com.thoughtworks.xstream.converters.reflection.SerializationMethodInvoker.callWriteObject(SerializationMethodInvoker.java:141)
at com.thoughtworks.xstream.converters.reflection.SerializableConverter.doMarshal(SerializableConverter.java:259)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:83)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:69)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:58)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller$1.convertAnother(AbstractReferenceMarshaller.java:84)
at hudson.util.RobustReflectionConverter.marshallField(RobustReflectionConverter.java:224)
at hudson.util.RobustReflectionConverter$2.writeField(RobustReflectionConverter.java:211)
... 161 more
Caused by: com.thoughtworks.xstream.converters.ConversionException: Could not call hudson.remoting.RemoteOutputStream.writeObject() : null
---- Debugging information ----
message : Could not call hudson.remoting.RemoteOutputStream.writeObject()
cause-exception : java.lang.NullPointerException
cause-message : null
-------------------------------
at com.thoughtworks.xstream.converters.reflection.SerializationMethodInvoker.callWriteObject(SerializationMethodInvoker.java:141)
at com.thoughtworks.xstream.converters.reflection.SerializableConverter.doMarshal(SerializableConverter.java:259)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.marshal(AbstractReflectionConverter.java:83)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:69)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:58)
at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:43)
at com.thoughtworks.xstream.core.AbstractReferenceMarshaller$1.convertAnother(AbstractReferenceMarshaller.java:88)
at com.thoughtworks.xstream.converters.reflection.SerializableConverter$1.writeToStream(SerializableConverter.java:140)
at com.thoughtworks.xstream.core.util.CustomObjectOutputStream.writeObjectOverride(CustomObjectOutputStream.java:84)
at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:343)
at hudson.util.StreamTaskListener.writeObject(StreamTaskListener.java:163)
at sun.reflect.GeneratedMethodAccessor1916.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at com.thoughtworks.xstream.converters.reflection.SerializationMethodInvoker.callWriteObject(SerializationMethodInvoker.java:135)
... 168 more
Caused by: java.lang.NullPointerException
at hudson.remoting.RemoteOutputStream.writeObject(RemoteOutputStream.java:82)
at sun.reflect.GeneratedMethodAccessor1917.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at com.thoughtworks.xstream.converters.reflection.SerializationMethodInvoker.callWriteObject(SerializationMethodInvoker.java:135)
... 182 more

For those of you who are terminating nodes manually, you can add something like this to your slave init script - it'll add a cron entry to shutdown if slave.jar isn't around.

(crontab -l 2>/dev/null; echo "*/5 * * * * sleep 120 ; ps -ef|grep -v grep|grep slave.jar >&1 > /dev/null || sudo -n shutdown -h now") | crontab -