Merge pull request #23522 from VladMasarik/patch-2

Updated ingress.md TLS section

Author: k8s-ci-robot

content/en/docs/concepts/services-networking/ingress.md

@@ -413,6 +413,13 @@ secure the channel from the client to the load balancer using TLS. You need to m
 sure the TLS secret you created came from a certificate that contains a Common
 Name (CN), also known as a Fully Qualified Domain Name (FQDN) for `https-example.foo.com`.
 
+{{< note >}}
+Keep in mind that TLS will not work on the default rule because the
+certificates would have to be issued for all the possible sub-domains. Therefore,
+`hosts` in the `tls` section need to explicitly match the `host` in the `rules`
+section.
+{{< /note >}}
+
 {{< codenew file="service/networking/tls-example-ingress.yaml" >}}
 
 {{< note >}}