,
  &#34;domains&#34;: [
    &#34;*&#34;
  ],
  &#34;routes&#34;: [
    {
      &#34;match&#34;: {
        &#34;prefix&#34;: &#34;/&#34;
      },
      &#34;route&#34;: {
        &#34;cluster&#34;: &#34;PassthroughCluster&#34;
      }
    }
  ]
}
</code></pre></li></ul><p>Prior to Istio 1.3, there were no metrics reported or if metrics were reported
there were no explicit labels set when traffic hit these clusters, resulting in
lack of visibility in traffic flowing through the mesh.</p><p>The next section c