The LoadMaster includes a feature called content rules. When content rules are enabled, the LoadMaster will evaluate incoming traffic against a set of rules and makes routing and load balancing decisions based on the results. These rules are typically based on regular expressions and can, for instance, be used to (partially) match the hostname string (URL) of incoming traffic. The result is that, now, that URL can be used to determine where the traffic should be forwarded to.

Let’s clarify this with an example:

The above content rule would search the content of an incoming request for a pattern matching the regex expression: /^\/owa.*/.

Note: For more information on content rules in general, and further regex examples, refer to the Content Rules, Feature Description.

When, for example, the hostname string (URL) matches this expression, the configuration parameters of the Virtual Service (or SubVS) to which the content rule is assigned, will be used for routing and load balancing decisions.

SubVSs allow the creation of a flexible Virtual Service which leverages the use of multiple content matching rules to mix and match one or more applications.