If you wish to see the state of data at a given chain point, right click the chain point and select New probe…

The following dialog box appears:

To set a probe, you can specify CSV lists of variables and values that must be matched (or you can leave the fields blank to have the probe trigger on the next transaction through that chain point).

Variable can be surrounded by various special characters to indicate additional criteria. For example, consider a variable named VAR:

• !VAR : means that VAR is not equal to the selection value

• VAR* : means that the VAR content starts with the selection value

• *VAR : means that the VAR content ends with the selection value

• *VAR* : means that the VAR content contains the selection value

• VAR< : means that the VAR content is less than the selection value

• VAR> : means that the VAR content is greater than the selection value

For the < and > characters, the value will first be attempted to converted to a number. If that succeeds, full numeric comparisons are performed. If not, a lexicalist comparison will take place.

You can also select the occurrence number of the probe to see. This is especially useful when debugging loops.

By default, only the first 100 characters of any variable is recorded.

Once the probe is set, the chain point changes color to yellow:

It will stay yellow until a matching transaction reaches the chain point, at which point it will turn red:

You can now see the variables as they were when they reached the probe. To do this, right click on the chain point again and select View probe:

A dialog box appears with the variable information:

To close the dialog box, click the X in the top right corner.

Given that the live view of the rules constantly polls the target server for updates every 5 seconds, it is not recommended to keep many live view rule sets open at the same time. The performance impact on the target X Engine has the potential to be significant.

Provided the user has access to trace and performance data for a given server, the user can explore the live performance of a running server and can insert probes to see the live data for any given chain point through-out the rules. This is an excellent debugging tool that can even be used on productions servers.

To obtain live performance data, go to the server status and click to retrieve the server performance as normal. If you have the ability to trace and view performance for the server, some additional options will show:

In the View live section, click on View Rules Performance to see the live performance of your rules:

You can not only see the number of transactions flowing through each rule, you can also see the live properties of the rule set in use. The data and rule sets visualized for the live view are all extracted from the server. The transaction counts will update every 5 seconds.