et to BlackHoleCluster
to indicate that this traffic was blocked by the mesh. Is is interesting to
note that for the BlackHole cluster case, other TCP related metrics like
<code>istio_tcp_connections_opened_total</code> are not increased as there&rsquo;s no
connection that is ever established.</p><p>Monitoring these metrics can help operators easily understand all the external
services consumed by the applications in their cluster.</p><nav id=see-also><h2>See also</h2><div class=see-also><div class=entry><p