I seem to deal with add request all week long, and frequently these requests are only partially baked as far as connectivity is concerned. I wrote this quick tool to have each polling server test connectivity to a list of IP addresses prior to going through the trouble of adding inventory only to find out that it's not reachable. This has saved me some time as I can run the script, go do other things, then send the request back until it's complete.
You need to enable-psremoting, and add your management hosts to the trustedhosts on the polling servers. For me, I add my primary server name, and my workstation name to each trustedhosts on my polling engines.
ps> set-item wsman:localhost\client\trustedhosts -value "orionserver1, myworkstation". You can open it up to a broader audience at your discretion.
This will produce a list of pass/fails for each requested IP's connectivity from each polling engine.
Update the $pingBoxes array to contain your Orion polling servers, and the $targetBoxes array to contain your list of test ping IPs.