Testing Monitors

To test a monitor in the main list, click the "Test" button in the main window.

You can also test the settings of a monitor you're editing or creating, by clicking the "Test These Settings" button in the Monitor Editor.

The following dialog box will appear, and the test will begin immediately:

Service Monitor checks services in the following manner:

1. First, the monitor initiates a connection on the specified IP address and port (usually the default IP address for this computer, and the default port for the desired type of service).
2. If this is successful, the monitor may request information from the service. For example, the Web (HTTP) monitor asks for a specific web page, and the Mail Transfer (SMTP) monitor can optionally check to see if a specified mailbox exists. (Not all service types need this step.)

The test dialog shows these requests, as well as the responses from the service. The requests are always preceded with ">>>", and the responses are usually preceded with a number indicating the type of response. (See "Troubleshooting" below for more information.)

3. Finally, the monitor waits for the requested information and checks to see if it matches what was requested.

If all steps pass, the last line of the test reports "Test successful". You may then click the "Test Again" button to perform an additional test, or click "Done" to dismiss the test dialog.

If the test is not successful, the last line of the test reports either a standard error code, or the word "Failed" with a reason for the failure in parentheses.

Troubleshooting

Because Internet communications have many steps, test failures can occur at several different stages. The lines in the test dialog can help you track down the exact point the failure occurs.A comprehensive list of failures is impossible, but you can use the status lines in the test dialog to help track down where the failure is occuring.

Here are some common failure situations and how to troubleshoot them:

Error 102

This standard error code indicates that the monitor was unable to initiate a connection with the service. To troubleshoot these failures, try the following:

1. Verify that your service is running using another application, for example a web browser to see if your web server is running.
2. Double-check the monitor's IP address and port values.

Timeouts

If a connection is established, but never completes in time (see Preferences for more information), it may be that the service is not returning the information expected by the monitor.

1. Check your preferences to ensure you're giving the service enough time to finish responding (see Preferences for more information).
2. Examine the lines of the test to see where the timeout is occurring. It might be that your service doesn't support that particular request.

Errors from the service

If the "Failed" message appears, look at the lines before it in the list. For example, the following error can occur if a Mail Transfer (SMTP) service can't find a desired user:

Note that most messages from the service are preceded with a number like "220" or "250". Numbers in the 200s generally indicate normal information responses, and numbers in the 400s and 500s indicate errors. In this case, the service responds with "550 user unknown", meaning that this monitor checks for a non-existent user "jamesk".

Each type of service will have its own set of response codes. Here are some links to pages with codes for the most common types of services:

File Transfer (FTP)

http://ftplab.com/ftperrorcodes.htm

Web (HTTP and HTTPS)

http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html

Mail Transfer (SMTP)

http://www.networksorcery.com/enp/protocol/smtp.htm