The Setup:
We have two Servers. They are on different subnets, but can still communicate with each other.
The Issue:
Server 1 used to query Server 2’s Services with a ServiceController.Status call successfully, until our IT Staff tightened the firewall between the two subnets (we lost RDP access to Server 2 and ServiceController.Status calls from Server 1 to Server 2 started to fail).
IT has relaxed the firewall a bit (so RDP to Server 2 now works), but our ServiceController.Status calls still fail (The error is: Cannot open Service Control Manager on Computer).
The Question:
How does ServiceProcess.ServiceController perform it’s tasks? Does it use a special TCP Port when doing it’s work?
I am suspecting that the firewall is preventing remote access to the Service Controller on Server 2, so I’d like to tell our IT staff what ports we need opened.
I’ve looked at the MSDN page, but I haven’t been able to find out what I need.
Check out this TechNet article: http://technet.microsoft.com/en-us/library/cc738291(v=ws.10).aspx#w2k3tr_rpc_how_vfae. It contains a table of the protocols and their associated socket ports that can be used by RPC, which the .NET ServiceController class depends on. Your IT staff probably, in their exuberance, closed one or more of these ports (some are more vital than others, depending on how many other options are available), rendering RPC inoperable.