Version 

4.0

2.3  Reconfiguring your site based on 

Traffic Load 

In this example, we'll monitor the performance of the JSP pages on a 

website.  If the performance drops below an acceptable level, we'll use 

the Control API to enable a TrafficScript rule that prevents more users 

from logging into the website.  Once performance climbs back to an 

acceptable level, the Control API application can disable the rule. 

The TrafficScript Rule 

To prevent users from logging into the site, we could use a TrafficScript 

rule similar to the following: 

$path = http.getPath(); 

if( string.endsWith( $path, "login.jsp" ) ) { 

   http.redirect( "/content/login_disabled.html" ); 

} 

Add this rule to the Rules catalog, calling it `Disable Login'.  Configure it 

as a request rule for your virtual server, but set it to be disabled.  The 

ZXTM Control API application will use the Virtual Server getRules() and 

setRules() functions to modify the `enabled' status of the rule. 

Monitoring Performance 

Performance of the web application can be monitored in a variety of 

ways: 

Using statistics gathered from the web application itself. 

Using an external monitoring tool to send probe requests. 

Monitoring the node response times using SNMP and ZXTM's Service 

Level Monitoring capability. 

Using the SNMP or email alerts raised by ZXTM's Service Level 

Monitoring capability to drive the Control API applications directly. 

Enabling and Disabling the Rule 

The following Control API code retrieves the list of response rules that 

the named virtual server is using.  It searches for the rule named 

`Disable Login' and enables it.  If the rule is not present, it adds it as the 

first rule to be executed. 

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