The MOM Remote Prerequisite Checker tool (MOMNetChk.exe) is pretty cool for checking the MOM agent to make sure the required ports and services are available. It even runs a ping test.
You can use the MOM Remote Prerequisite Checker (MOMNetChk.exe) tool in the Microsoft Operations Manager Resource Kit, available from http://www.microsoft.com/mom/downloads/2005/reskit/default.mspx, to scan a computer for the status of ports used by the MOM service and related services. The tool also provides information on the status of services that the MOM service depends on. This information can be displayed in a report window or saved in a log file called MOMSCAN.log.
1. Run MOMNetChk.exe and enter the target computer name in the Computer Name window. Click the Run Scan button. If a log is needed, click the Save to Log File button and select the desired log file location.
2. Expand the nodes in the left pane and you will see the tests that were run, the outcome and details when you click each test.
Note: The MOMNetChk.exe tool does not report specific errors, it simply tests the status of essential network and service components.
This information will soon be part of KB article
904866 "How to install and manage Microsoft Operations Manager 2005 agent computers that are behind a firewall or in an untrusted domain" http://support.microsoft.com/default.aspx?scid=kb;EN-US;904866
Manageability Knowledge Engineer