<p>The documentation does not specify how to add an intermediate SSL certificate: <a href="https://kubernetes.io/docs/concepts/services-networking/ingress/#tls" rel="noreferrer">https://kubernetes.io/docs/concepts/services-networking/ingress/#tls</a></p>

<p>I suppose the next step would be to read the Kubernetes source code.</p>

<p>If you add multiple certificates in <code>tls.cert</code> key in Kubernetes TLS Ingress Configuration. Please do this like this</p>

<pre><code>-----BEGIN CERTIFICATE-----
&lt;put your certificate value in a single line &gt;
-----END CERTIFICATE-----
-----BEGIN INTERMEDIATE CERTIFICATE-----
&lt;put your certificate value in a single line&gt;
-----END INTERMEDIATE CERTIFICATE-----
</code></pre>

<p>Otherwise, you'll get an error in ssl cert chain validation.</p>

<p>Always put main certificate first.</p>
