<p>I have added Istio to an existing GKE cluster. This cluster was initially deployed from the GKE UI with Istio "disabled".</p>

<p>I have deployed Istio from the CLI using kubectl and while everything works fine (istio namespace, pods, services, etc...) and I was able later on to deploy an app with Istio sidecar pods etc..., I wonder why the GKE UI still reports that Istio is <code>disabled</code> on this cluster. This is confusing - in effect, Istio is deployed in the cluster but the UI reports the opposite.</p>

<p>Is that a GKE bug ?</p>

<p>Deployed Istio using:
kubectl apply -f install/kubernetes/istio-auth.yaml</p>

<p>Deployment code can be seen here:</p>

<p><a href="https://github.com/hassanhamade/istio/blob/master/deploy" rel="nofollow noreferrer">https://github.com/hassanhamade/istio/blob/master/deploy</a></p>

hassan hamade
<p>From my point of view this doesn't look as  a bug, I assume that the status is <code>disabled</code> because you have deployed a custom version of Istio on you cluster. This flag should be indicating the status of the GKE managed version. </p>

<p>If you want to update your cluster to use GKE managed version, you can do it as following:</p>

<p>With TLS enforced</p>

<pre><code>gcloud beta container clusters update CLUSTER_NAME \
    --update-addons=Istio=ENABLED --istio-config=auth=MTLS_STRICT
</code></pre>

<p>or</p>

<p>With mTLS in permissive mode </p>

<pre><code>gcloud beta container clusters update CLUSTER_NAME \
    --update-addons=Istio=ENABLED --istio-config=auth=MTLS_PERMISSIVE
</code></pre>

<p>Check <a href="https://cloud.google.com/istio/docs/istio-on-gke/installing#creating_a_cluster_with_istio_on_gke" rel="nofollow noreferrer">this</a> for more details.</p>

<p>Be careful since you already have deployed Istio, enabling the GKE managed one may cause issues.</p>
