I am testing the trial version of PRTG and have run into a bizarre problem. Both the PRTG computer and the target computer are VM guests on a Windows 2008 R2 Hyper-V server. I want to monitor a few WMI values, and have a Group Policy rule to allow incoming WMI, also to allow echo requests. These settings work fine for Spiceworks, but PRTG only retrieves WMI info when I also open port 1341 TCP.
I found this port number by examining the Windows Firewall log. This error appeared:
2011-03-08 17:14:58 DROP TCP 192.168.60.7 192.168.60.2 1030 1341 413 AP 3286503447 2969398679 65264 - - - RECEIVE
It seems there is an initial contact on port 135, then more contact on 1341 ... is this normal?