I have a similar issue when trying to configure a cloud VM as slave and get the following error:
java.lang.ClassCastException: hudson.slaves.SlaveComputer cannot be cast to hudson.slaves.AbstractCloudComputer at com.nirima.jenkins.plugins.docker.strategy.DockerOnceRetentionStrategy.start(DockerOnceRetentionStrategy.java:24) at hudson.model.AbstractCIBase.updateComputer(AbstractCIBase.java:133) at hudson.model.AbstractCIBase.access$000(AbstractCIBase.java:45) at hudson.model.AbstractCIBase$2.run(AbstractCIBase.java:192) at hudson.model.Queue._withLock(Queue.java:1342) at hudson.model.Queue.withLock(Queue.java:1219) at hudson.model.AbstractCIBase.updateComputerList(AbstractCIBase.java:175) at jenkins.model.Jenkins.updateComputerList(Jenkins.java:1573) at jenkins.model.Nodes$8.run(Nodes.java:333) at hudson.model.Queue._withLock(Queue.java:1342) at hudson.model.Queue.withLock(Queue.java:1219) at jenkins.model.Nodes.load(Nodes.java:324) at jenkins.model.Jenkins$16.run(Jenkins.java:3091) at org.jvnet.hudson.reactor.TaskGraphBuilder$TaskImpl.run(TaskGraphBuilder.java:169) at org.jvnet.hudson.reactor.Reactor.runTask(Reactor.java:282) at jenkins.model.Jenkins$7.runTask(Jenkins.java:1090) at org.jvnet.hudson.reactor.Reactor$2.run(Reactor.java:210) at org.jvnet.hudson.reactor.Reactor$Node.run(Reactor.java:117) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748) Caused: org.jvnet.hudson.reactor.ReactorException at org.jvnet.hudson.reactor.Reactor.execute(Reactor.java:269) at jenkins.InitReactorRunner.run(InitReactorRunner.java:47) at jenkins.model.Jenkins.executeReactor(Jenkins.java:1124) at jenkins.model.Jenkins.<init>(Jenkins.java:929) at hudson.model.Hudson.<init>(Hudson.java:86) at hudson.model.Hudson.<init>(Hudson.java:82) at hudson.WebAppMain$3.run(WebAppMain.java:235) Caused: hudson.util.HudsonFailedToLoad at hudson.WebAppMain$3.run(WebAppMain.java:252)
even worse, I tried to rebounce the jenkins server and got the same error. Now I can not restart jenkins server anymore. Glad that it is on my local test environment.
OS: centos:7
jenkins server: 2.69
I seem to have the same error, bit with a different stacktrace
I am not able to start jenkins properly
OS: RHEL 6.6
Jenkins: 1.596.2
Java: 1.7.0_79