Jenkins error - Remote call on slave fails
<p>Jenkins build fails with error "FATAL: java.io.IOException: Remote call on "slave_node" failed hudson.remoting.RemotingSystemException: java.io.IOException: Remote call on "slave_node" failed.</p>

<pre><code>at   hudson.remoting.RemoteInvocationHandler.invoke(RemoteInvocationHandler.java:195)
at com.sun.proxy.$Proxy80.setProxy(Unknown Source)
at org.jenkinsci.plugins.gitclient.RemoteGitImpl.setProxy(RemoteGitImpl.java:856)
at org.jenkinsci.plugins.gitclient.Git.getClient(Git.java:133)
at hudson.plugins.git.GitSCM.createClient(GitSCM.java:677)
at hudson.plugins.git.GitSCM.createClient(GitSCM.java:669)
at hudson.plugins.git.GitSCM.checkout(GitSCM.java:1010)
at hudson.scm.SCM.checkout(SCM.java:484)
at hudson.model.AbstractProject.checkout(AbstractProject.java:1270)
at hudson.model.AbstractBuild$AbstractBuildExecution.defaultCheckout(AbstractBuild.java:622)
at jenkins.scm.SCMCheckoutStrategy.checkout(SCMCheckoutStrategy.java:86)
at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:528)
at com.tikal.jenkins.plugins.multijob.MultiJobBuild$MultiJobRunnerImpl.run(MultiJobBuild.java:134)
at hudson.model.Run.execute(Run.java:1759)
at com.tikal.jenkins.plugins.multijob.MultiJobBuild.run(MultiJobBuild.java:73)
at hudson.model.ResourceController.execute(ResourceController.java:89)
at hudson.model.Executor.run(Executor.java:240)
Caused by: java.io.IOException: Remote call on ffuas4eng01 failed
at hudson.remoting.Channel.call(Channel.java:760)
at hudson.remoting.RemoteInvocationHandler.invoke(RemoteInvocationHandler.java:179)
... 16 more
Caused by: java.lang.NoClassDefFoundError: Could not initialize class hudson.util.Secret
at sun.misc.Unsafe.ensureClassInitialized(Native Method)
at sun.reflect.UnsafeFieldAccessorFactory.newFieldAccessor(UnsafeFieldAccessorFactory.java:43)
at   sun.reflect.ReflectionFactory.newFieldAccessor(ReflectionFactory.java:142)
at java.lang.reflect.Field.acquireFieldAccessor(Field.java:1088)
at java.lang.reflect.Field.getFieldAccessor(Field.java:1069)
at java.lang.reflect.Field.getLong(Field.java:611)
at java.io.ObjectStreamClass.getDeclaredSUID(ObjectStreamClass.java:1707)
at java.io.ObjectStreamClass.access$700(ObjectStreamClass.java:72)
at java.io.ObjectStreamClass$2.run(ObjectStreamClass.java:484)
at java.io.ObjectStreamClass$2.run(ObjectStreamClass.java:472)
at java.security.AccessController.doPrivileged(Native Method)
at java.io.ObjectStreamClass.&lt;init&gt;(ObjectStreamClass.java:472)
at java.io.ObjectStreamClass.lookup(ObjectStreamClass.java:369)
at java.io.ObjectStreamClass.initNonProxy(ObjectStreamClass.java:598)
at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1623)
at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1518)
at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1774)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1351)
at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2000)
at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1924)
at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1801)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1351)
at java.io.ObjectInputStream.readArray(ObjectInputStream.java:1707)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1345)
at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2000)
at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1924)
at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1801)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1351)
at java.io.ObjectInputStream.readObject(ObjectInputStream.java:371)
at hudson.remoting.UserRequest.deserialize(UserRequest.java:185)
at hudson.remoting.UserRequest.perform(UserRequest.java:99)
at hudson.remoting.UserRequest.perform(UserRequest.java:49)
at hudson.remoting.Request$2.run(Request.java:324)
at hudson.remoting.InterceptingExecutorService$1.call(InterceptingExecutorService.java:68)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
at ......remote call to ffuas4eng01(Native Method)
at hudson.remoting.Channel.attachCallSiteStackTrace(Channel.java:1356)
at hudson.remoting.UserResponse.retrieve(UserRequest.java:221)
at hudson.remoting.Channel.call(Channel.java:752)
... 17 more
</code></pre>

<p>I don't understand the issue. Could someone help me? The master and slave are correctly set up as far as i can see. Thanks in advance!</p>