his to ensure that the
<em>reviews</em> service always calls the <em>ratings</em> service. In addition, route all the traffic destined to the <em>ratings</em>
service to <em>ratings v2</em> that uses your database.</p><p>Specify the routing for both services above by adding two
<a href=/v1.18/docs/reference/config/networking/virtual-service/>virtual services</a>. These virtual services are
specified in <code>samples/bookinfo/networking/virtual-service-ratings-mongodb.yaml</code> of an Istio release archive.