Troubleshooting Your Link Monitor

Your link monitor must be configured correctly to be a useful source of information about network connectivity.

• Configuring and starting a link monitor are separate processes. When you create a link monitor, you specify the characteristics and properties of the link monitor. The link monitor is not operational until it is started. Monitors can be started manually from the Tools menu in the Administrator window. Usually, they are started from the command line, from a batch file, or a program item in the Startup group on a dedicated server.
• Link monitors function only when they are started and open. If you close the link monitor window, you stop the monitor. It no longer sends or times ping messages or writes to the log.
• The configuration specifies the destination servers to which ping messages are sent; it does not specify which server is the source of the ping message. The source is determined by your entry in the Connect to Server box when you start the link monitor. The same link monitor configuration will be monitoring different connections if started with different source servers.
• Link monitors assign a status of warning and alerts based solely on the thresholds you establish on the link monitor's Bounce property page. If the threshold is not appropriate for every link monitored, the status is not accurate. If one of the routes requires a longer or shorter threshold, create a separate link monitor.
• Ping messages sent to servers in foreign systems should be received by an application that replies to it. If the ping message is sent to a nonexistent address, a non-delivery report (NDR) is interpreted as a sign that the link is operational. However, when NDRs are returned from foreign systems, it is not clear which host actually generated the NDR and which connection has been tested. Send a message along the route of the ping message and examine the NDR to determine the replying host.
• If the system clock is changed by more than a few minutes, restart the monitors. Otherwise, pending messages appear to be late, or connections appear to be down until the previous time is reached.