<p>Let's say a Istio enabled Service <code>A</code> exposes a port <code>8080</code> which is named <code>http</code> and as such Istio performs L7 load balancing when accessing it from inside of the mesh.</p>

<p>I'd like to know if there is a way to access this <code>8080</code> port from a pod/service <code>B</code> that doesn't have the Istio sidecar. In such case the traffic would be:
<code>
B -&gt; A Envoy -&gt; A
</code>
or
<code>
B -&gt; A
</code>
This way, I'm able to access an <code>A</code>'s port that is not named <code>http</code> (i.e., only L4 load balancing is in place)</p>

<p>My particular use-case is that I have Prometheus (not running in the mesh) with Prometheus Operator scraping the services running in the mesh directly (Istio Mixer is not involved; the services expose their own business logic metrics). It works for me only and only if a given service doesn't name its port <code>http</code>.</p>

<p>If you have auth (mTLS) enabled it doesn't work, by design, as in that case Istio tries to protect all service to service communication.</p>

<p>You can turn auth off, and if that doesn't help, also try with the Istio 0.2.4 release candidate (or whichever is the latest at the time you read this, see <a href="https://github.com/istio/istio/releases" rel="nofollow noreferrer">https://github.com/istio/istio/releases</a>) and see if the problem persists, if it does please file an issue at <a href="https://github.com/istio/issues/issues/new" rel="nofollow noreferrer">https://github.com/istio/issues/issues/new</a></p>

<p>In 0.3 (and possibly earlier) we'll let you have fine grain control over mTLS.</p>
