在使用openstack4j连接调用OpenStack时，报错

具体部分报错：

Exception in thread "main" ConnectionException{message=RESTEASY004655: Unable to invoke request, status=0}
    at org.openstack4j.connectors.resteasy.HttpExecutorServiceImpl.invoke(HttpExecutorServiceImpl.java:57)
    at org.openstack4j.connectors.resteasy.HttpExecutorServiceImpl.execute(HttpExecutorServiceImpl.java:31)
    at org.openstack4j.core.transport.internal.HttpExecutor.execute(HttpExecutor.java:51)
    at org.openstack4j.openstack.internal.BaseOpenStackService$Invocation.execute(BaseOpenStackService.java:213)
    at org.openstack4j.openstack.internal.BaseOpenStackService$Invocation.execute(BaseOpenStackService.java:207)
    at 

.............................
Caused by: java.net.UnknownHostException: controller
    at java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method)
    at java.net.InetAddress$2.lookupAllHostAddr(InetAddress.java:928)
    at java.net.InetAddress.getAddressesFromNameService(InetAddress.java:1323)
    at java.net.InetAddress.getAllByName0(InetAddress.java:1276)
    at java.net.InetAddress.getAllByName(InetAddress.java:1192)
    at java.net.InetAddress.getAllByName(InetAddress.java:1126)
 

OpenStack环境：通过在两台虚拟机上搭建的OpenStack环境，两台虚拟机的主机名分别为controller、compute。而这里报错为未知主机。

解决：

（1）在Windows下打开windws/system32/driver/etc/hosts,添加以下内容

        虚拟机IP controller
        虚拟机IP compute

（2）linux服务器

       vi  /etc/hosts