two example tracing providers.
      - name: &#34;localtrace&#34;
        zipkin:
          service: &#34;zipkin.istio-system.svc.cluster.local&#34;
          port: 9411
          maxTagLength: 56
      - name: &#34;cloudtrace&#34;
        stackdriver:
          maxTagLength: 256
</code></pre><p>为了方便，Istio 默认设置随附了几个开箱即用的提供程序：</p><table><thead><tr><th>提供程序名称</th><th>功能</th></tr></thead><tbody><tr><td><code>prometheus</code></td><td>指标</td></