Description of problem:
Met "500 - Internal Server Error" when access "Administration Console" of jboss-wildfly-9 kitchensink quickstart 

Version-Release number of selected component (if applicable):
devenv_5514
jboss-wildfly-9

How reproducible:
always

Steps to Reproduce:
1.Create a jboss-wildfly-9 kitchensink quickstart 
rhc app create kitchensink jboss-wildfly-9 
cd kitchensink
git remote add upstream -m master git://github.com/openshift/kitchensink-example.git
git pull -s recursive -X theirs upstream master
2.Access the app's url
3.Click "Administration Console"

Actual results:
Step 3:
Will meet "500 - Internal Server Error"

Expected results:
Should acess Administration Console

Additional info：
Find logs in wildfly/logs/server.log
--------------------------------------------------------------
 ERROR [org.jboss.msc.service.fail] (MSC service thread 1-2) MSC000001: Failed to start service jboss.jgroups.channel.ee: org.jboss.msc.service.StartException in service jboss.jgroups.channel.ee: java.security.PrivilegedActionException: java.lang.Exception: Property assignment of initial_hosts in TCPPING with original property value null and converted to null could not be assigned
        at org.wildfly.clustering.jgroups.spi.service.ChannelBuilder.start(ChannelBuilder.java:79)
        at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1948)
        at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1881)
        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)
Caused by: java.security.PrivilegedActionException: java.lang.Exception: Property assignment of initial_hosts in TCPPING with original property value null and converted to null could not be assigned
        at org.wildfly.security.manager.WildFlySecurityManager.doChecked(WildFlySecurityManager.java:638)
        at org.jboss.as.clustering.jgroups.JChannelFactory.createChannel(JChannelFactory.java:99)
        at org.wildfly.clustering.jgroups.spi.service.ChannelBuilder.start(ChannelBuilder.java:77)
        ... 5 more
Caused by: java.lang.Exception: Property assignment of initial_hosts in TCPPING with original property value null and converted to null could not be assigned
        at org.jgroups.stack.Configurator.resolveAndAssignField(Configurator.java:1153)
        at org.jgroups.stack.Configurator.createLayer(Configurator.java:444)
        at org.jgroups.stack.Configurator.createProtocols(Configurator.java:398)
        at org.jgroups.stack.Configurator.setupProtocolStack(Configurator.java:90)
        at org.jgroups.stack.Configurator.setupProtocolStack(Configurator.java:57)
        at org.jgroups.stack.ProtocolStack.setup(ProtocolStack.java:477)
        at org.jgroups.JChannel.init(JChannel.java:854)
        at org.jgroups.JChannel.<init>(JChannel.java:159)
        at org.jboss.as.clustering.jgroups.JChannelFactory$1.run(JChannelFactory.java:96)
        at org.jboss.as.clustering.jgroups.JChannelFactory$1.run(JChannelFactory.java:93)
        at org.wildfly.security.manager.WildFlySecurityManager.doChecked(WildFlySecurityManager.java:634)
        ... 7 more