JBoss ON agent fails startup with "java.net.UnknownHostException"

Issue

• Agent fails to start with:

2016-06-02 09:01:38,822 FATAL [main] (org.rhq.enterprise.agent.AgentMain)- {AgentMain.startup-error}The agent encountered an error during startup and must abort
java.lang.RuntimeException: Error setting up server invoker SocketServerInvoker[UNINITIALIZED]
    at org.jboss.remoting.ServerInvoker.create(ServerInvoker.java:854)
    at org.jboss.remoting.transport.Connector.init(Connector.java:411)
    at org.jboss.remoting.transport.Connector.create(Connector.java:815)
    at org.rhq.enterprise.communications.ServiceContainer.setupServerConnector(ServiceContainer.java:1263)
    at org.rhq.enterprise.communications.ServiceContainer.start(ServiceContainer.java:596)
    at org.rhq.enterprise.communications.ServiceContainer.start(ServiceContainer.java:514)
    at org.rhq.enterprise.agent.AgentMain.startCommServices(AgentMain.java:2524)
    at org.rhq.enterprise.agent.AgentMain.start(AgentMain.java:715)
    at org.rhq.enterprise.agent.AgentMain.main(AgentMain.java:461)
Caused by: java.net.UnknownHostException: content
    at java.net.Inet4AddressImpl.lookupAllHostAddr(Native Method)
    at java.net.InetAddress$1.lookupAllHostAddr(InetAddress.java:849)
    at java.net.InetAddress.getAddressFromNameService(InetAddress.java:1202)
    at java.net.InetAddress.getAllByName0(InetAddress.java:1153)
    at java.net.InetAddress.getAllByName(InetAddress.java:1083)
    at java.net.InetAddress.getAllByName(InetAddress.java:1019)
    at java.net.InetAddress.getByName(InetAddress.java:969)
    at org.jboss.remoting.ServerInvoker.setup(ServerInvoker.java:1019)
    at org.jboss.remoting.transport.socket.SocketServerInvoker.setup(SocketServerInvoker.java:157)
    at org.jboss.remoting.ServerInvoker.create(ServerInvoker.java:850)