Failover Recommendations

ATG guarantees that you will receive recommendations in a timely fashion twenty-four hours a day, seven days a week. In order to ensure your recommendations are always served, ATG has developed a failover protocol that will maintain recommendation consistency, even if our servers are completely down.

What is Failover?

ATG Recommendations regularly updates a static file, a failover file, that contains a subset of your most popular products. In the event that ATG Recommendations experiences difficulties that could lead to the delay or cessation of recommendations, failover will immediately and seamlessly take effect. Failover will then generate recommendations by choosing a random selection of products from the failover file. This file is stored both locally and on Akamai web servers, so it is guaranteed to be available at all times.

When recommendation response times return to an acceptable level, failover will release control of recommendations back to the ATG Recommendations engine.

Customizing Failover

By default, failover is enabled and set to respond if ATG Recommendations take longer than 5000 milliseconds to return. This timeout does not only reflect the time the ATG servers take to respond, but also the speed of the connection and the time it takes the rest of the page to load. You can override these defaults and customize failover behavior by adding a -failover definition to your ATG Recommendations configuration. The -failover data type can have one of three definitions: true, false, or it can have a sublist of configuration options. Again, the default value for -failover is true.

If you would like to disable failover, you may do so by setting the -failover value to false, as in the following example:

    <div id="cs-cfg" >
      <dl class="cs-cfg">
        <dt>retailerId</dt><dd>Your Retailer Id</dd>
        <dt>-failover</dt><dd>false</dd>
      </dl>
    </div>

In order to change the default failover settings, you may define a subconfiguration list for the -failover flag. Following is a list of configuration options and examples.

timeout: The amount of time to wait for recommendations before switching to failover. The default timeout is set to 5000 milliseconds. For example, if you wished to wait three seconds before switching to failover recommendations, you could use the following code:

    <div id="cs-cfg" >
      <dl class="cs-cfg">
        <dt>retailerId</dt><dd>Your Retailer Id</dd>
        <dt>-failover</dt><dd>
            <dl>
                  <dt>timeout</dt><dd>3000</dd>
            </dl>
          </dd>
      </dl>
    </div>

skip-recommendations: This is for testing only. Enabling this flag will bypass the ATG Recommendations engine, forcing the return of failover recommendations. You can force the return of failover recommendations using the following code:

    <div id="cs-cfg" >
      <dl class="cs-cfg">
        <dt>retailerId</dt><dd>Your Retailer Id</dd>
        <dt>-failover</dt><dd>
            <dl>
                <dt>skip-recommendations</dt>
            </dl>
        </dd>
      </dl>
    </div>