title: Istio: failed calling admission webhook Address is not allowed
body: <p>I am getting the following error while creating a gateway for the sample bookinfo application</p>
  
  <blockquote>
    <p>Internal error occurred: failed calling admission webhook
    "pilot.validation.istio.io": Post
    <a href="https://istio-galley.istio-system.svc:443/admitpilot?timeout=30s" rel="nofollow noreferrer">https://istio-galley.istio-system.svc:443/admitpilot?timeout=30s</a>:
    Address is not allowed</p>
  </blockquote>
  
  <p>I have created a EKS poc cluster using two node-groups (each with two instances), one with t2.medium and another one is with t2.large type of instances in my dev AWS account using two subnets with /26 subnet with default VPC-CNI provided by EKS</p>
  
  <p>But as the cluster is growing with multiple services running, I started facing issues of IPs not available (as per docs default vpc-cni driver treat pods as an EC2 instance)</p>
  
  <p>to avoid same I followed following post to change networking from default to weave</p>
  
  <p><a href="https://medium.com/codeops/installing-weave-cni-on-aws-eks-51c2e6b7abc8" rel="nofollow noreferrer">https://medium.com/codeops/installing-weave-cni-on-aws-eks-51c2e6b7abc8</a></p>
  
  <p>because of same I have resolved IPs unavailability issue,</p>
  
  <p>Now after network reconfiguration from vpc-cni to weave</p>
  
  <p>I am started getting above issue as per subject line for my service mesh configured using Istio</p>
  
  <p>There are a couple of services running inside the mesh and also integrated kiali, prometheus, jaeger with the same.</p>
  
  <p>I tried to have a look at Github (<a href="https://github.com/istio/istio/issues/9998" rel="nofollow noreferrer">https://github.com/istio/istio/issues/9998</a>) and docs
  (<a href="https://istio.io/docs/ops/setup/validation/" rel="nofollow noreferrer">https://istio.io/docs/ops/setup/validation/</a>), but could not get a proper valid answer.</p>
  
  <p>Let me if anyone face this issue and have partial/full solution on this.</p>