title: How to fix : "command terminated with exit code 255"
body: <p>I want to user istio on GKE.
  But my istioctl has some errors.</p>
  
  <p>Istio version: 1.2.2
  Gke version: 1.12.8-gke.10</p>
  
  <pre><code>$ istioctl version
  client version: 1.2.2
  Error: 8 errors occurred:
      * error execing into istio-citadel-7cbd68dc58-7q4rq citadel container: command terminated with exit code 255
      * error execing into istio-egressgateway-76bd65699f-lwrr4 istio-proxy container: command terminated with exit code 255
      * error execing into istio-galley-848d6b698c-2kcrn galley container: container galley is not valid for pod istio-galley-848d6b698c-2kcrn
      * error execing into istio-ingressgateway-64d6cfc6cb-nsqb6 istio-proxy container: command terminated with exit code 255
      * error execing into istio-pilot-57c9ff7496-4qndd discovery container: command terminated with exit code 255
      * error execing into istio-policy-57bf7c4984-z6pks mixer container: command terminated with exit code 255
      * error execing into istio-sidecar-injector-9db9b45f5-4ndlk sidecar-injector-webhook container: command terminated with exit code 255
      * error execing into istio-telemetry-bf847c494-7p5hd mixer container: command terminated with exit code 255
  </code></pre>
  
  <p>Thanks you.</p>