Hi Peter,
We don't have have any port filtering blocking access to the virtual guest on port 135 (no firewall in between or inside the host). I am able to telnet this port correctly.
Here is the extract of the jetty-service log on the Balance proxy showing an error :
INFO | jvm 1 | 2013/07/31 10:12:05 | 151167375 [btpool0-31] ERROR com.akorri.bp.collectionserver.communication.WMI - Proxy Output File Access Error occurred whilst executing command: cscript//nologo//t:900C:/Program Files (x86)/NetApp/Balance/work/collection-server/code/scripts/windows/WmiToXml.vbs. Description: Unable to determine IP address for Hostname/FQDN.
INFO | jvm 1 | 2013/07/31 10:12:05 | 151167407 [btpool0-31] WARN org.springframework.remoting.support.RemoteInvocationTraceInterceptor - Processing of HttpInvokerServiceExporter remote call resulted in fatal exception: com.akorri.bp.collectionserver.proxy.IProxyService.runCommands
INFO | jvm 1 | 2013/07/31 10:12:05 | com.akorri.bp.collectionserver.exception.DeviceCommException: Proxy Output File Access Error occurred whilst executing command: cscript//nologo//t:900C:/Program Files (x86)/NetApp/Balance/work/collection-server/code/scripts/windows/WmiToXml.vbs.
As a sidenote, the Balance proxy is correctly resolving IP address and able to ping the guest virtual machines.