Japan Shah: failed

Monday, September 21, 2015

Jenkins - Unable to launch slave machine

Have you upgraded your jenkins to 1.6+ and unable to launch slave agents.

You might need to read this blog.

SSH Slaves Plugin / slaves.jar requires JDK 1.7

Upgrading Jenkins to 1.6+ doesn't allow Java version < 7.

Refer Blog: http://jenkins-ci.org/content/good-bye-java6

Due to which Jenkins failed to launch slave using SSH.

You might have received some error like below:

Caused by: java.lang.UnsupportedClassVersionError: hudson/slaves/SlaveComputer$SlaveVersion : Unsupported major.minor version 51.0
 at java.lang.ClassLoader.defineClass1(Native Method)
 at java.lang.ClassLoader.defineClass(ClassLoader.java:634)
 at java.lang.ClassLoader.defineClass(ClassLoader.java:480)
 at hudson.remoting.RemoteClassLoader.loadClassFile(RemoteClassLoader.java:338)
 at hudson.remoting.RemoteClassLoader.findClass(RemoteClassLoader.java:251)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:321)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:266)
 at java.lang.Class.forName0(Native Method)
 at java.lang.Class.forName(Class.java:264)
 at hudson.remoting.MultiClassLoaderSerializer$Input.resolveClass(MultiClassLoaderSerializer.java:113)
 at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1592)
 at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1513)
 at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1749)
 at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1346)
 at java.io.ObjectInputStream.readObject(ObjectInputStream.java:368)
 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:326)
 at hudson.remoting.InterceptingExecutorService$1.call(InterceptingExecutorService.java:68)
 at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
 at java.util.concurrent.FutureTask.run(FutureTask.java:166)
 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)
[09/21/15 13:34:57] Launch failed - cleaning up connection

Solution:

Log on to slave machine manually:

Download Java JDK 1.7 and extract it on home directory

```
Goto Jenkins Portal
```
```
Goto Manage your Node page
```

Goto "Advanced" settings under "Launch method" section

specify JavaPath to Java7 directory of remote(slave) machine

e.g /home/{user}/jdk1.7.0_79/bin/java

```
Relaunch Slave Agent
```

JavaPath is the important property that you're looking for fix, shown in the image below:

Friday, July 10, 2015

Eclipse Perforce SSL handshake failed Invalid SSL session ? Solution?

Problem: SSL handshake: invalid SSL session - eclipse perforce integration

Issue: JVM used by Eclipse not able to exchange perforce SSL certificate

Solution: Replace JCE files for your version of JAVA - follow the steps below

Backup Existing Libraries (Optional):

$JAVA_HOME/jre/lib/security/local_policy.jar
$JAVA_HOME/jre/lib/security/US_export_policy.jar

e.g. JCE location: C:\Program Files (x86)\Java\jre7\lib\security

Download & Replace JCE for your installed version of Java

Replace both the JCE jar files from the downloaded ZIP file.

Thanks to Govindaram PS

Original Reference: http://govindreloaded.blogspot.in/2015/02/perforce-eclipse-error-error-occurred.html