istio.io/content/en/docs/reference/config/analysis/ist0150/index.md

title	layout	owner	test
ExternalNameServiceTypeInvalidPortName	analysis-message	istio/wg-user-experience-maintainers	no

This message occurs for services of type ExternalName when the port doesn't follow Istio service port naming convention, the port is unnamed or the port is named tcp.

Example

You will receive this message:

{{< text plain >}} Warning [IST0150] (Service nginx.default) Port name for ExternalName service is invalid. Proxy may prevent tcp named ports and unmatched traffic for ports serving TCP protocol from being forwarded correctly. {{< /text >}}

when your cluster has the following service:

{{< text yaml >}} apiVersion: v1 kind: Service metadata: name: nginx spec: externalName: nginx.example.com ports:

• name: tcp port: 443 protocol: TCP targetPort: 443 type: ExternalName {{< /text >}}

In this example, the port name tcp follows the syntax: name: <protocol>. However, for ExternalName services, there is no service IP defined, so the SNI field is needed for routing.

How to resolve

• If you have an ExternalName service type, and the protocol is TCP, rename the port to <protocol>[-<suffix>] or <protocol> where protocol is https or tls. To learn more, review docs on explicit protocol selection.