ervices, each with multiple versions.
Three different versions of one of the microservices, <code>reviews</code>, have been deployed and are running concurrently.
To illustrate the problem this causes, access the Bookinfo app&rsquo;s <code>/productpage</code> in a browser and refresh several times.
You’ll notice that sometimes the book review output contains star ratings and other times it does not.
This is because without an explicit default service version to route to, Istio routes requests to all avail