Replace containervm with GCI as default master image for GCE clusters

cluster/common.sh

@@ -347,7 +347,7 @@ function find-release-tars() {
 
   # This tarball is used by GCI, Ubuntu Trusty, and CoreOS.
   KUBE_MANIFESTS_TAR=
-  if [[ "${KUBE_OS_DISTRIBUTION:-}" == "trusty" || "${KUBE_OS_DISTRIBUTION:-}" == "gci" || "${KUBE_OS_DISTRIBUTION:-}" == "coreos" ]]; then
+  if [[ "${OS_DISTRIBUTION:-}" == "trusty" || "${OS_DISTRIBUTION:-}" == "gci" || "${OS_DISTRIBUTION:-}" == "coreos" ]]; then
     KUBE_MANIFESTS_TAR="${KUBE_ROOT}/server/kubernetes-manifests.tar.gz"
     if [[ ! -f "${KUBE_MANIFESTS_TAR}" ]]; then
       KUBE_MANIFESTS_TAR="${KUBE_ROOT}/_output/release-tars/kubernetes-manifests.tar.gz"

cluster/gce/config-default.sh

@@ -35,11 +35,20 @@ PREEMPTIBLE_NODE=${PREEMPTIBLE_NODE:-false}
 PREEMPTIBLE_MASTER=${PREEMPTIBLE_MASTER:-false}
 
 
-OS_DISTRIBUTION=${KUBE_OS_DISTRIBUTION:-debian}
-MASTER_IMAGE=${KUBE_GCE_MASTER_IMAGE:-container-vm-v20160321}
+# Today the cluster startup scripts asssume the master and the nodes use the
+# same OS distro, thus same set of initialization instructions (e.g., metadata,
+# startup scripts, etc.). The current workaround is the hack in util.sh that
+# reloads <os_distro>/helper.sh in the gap between when the master is created
+# and when the nodes are created.
+# TODO(#26183): Provide a way to differentiate master OS distro and node OS
+# distro.
+OS_DISTRIBUTION=${KUBE_OS_DISTRIBUTION:-gci}
+# For GCI, leaving it blank will auto-select the latest GCI image on the `dev`
+# channel.
+MASTER_IMAGE=${KUBE_GCE_MASTER_IMAGE:-}
 MASTER_IMAGE_PROJECT=${KUBE_GCE_MASTER_PROJECT:-google-containers}
-NODE_IMAGE=${KUBE_GCE_NODE_IMAGE:-"${MASTER_IMAGE}"}
-NODE_IMAGE_PROJECT=${KUBE_GCE_NODE_PROJECT:-"${MASTER_IMAGE_PROJECT}"}
+NODE_IMAGE=${KUBE_GCE_NODE_IMAGE:-container-vm-v20160321}
+NODE_IMAGE_PROJECT=${KUBE_GCE_NODE_PROJECT:-google-containers}
 CONTAINER_RUNTIME=${KUBE_CONTAINER_RUNTIME:-docker}
 RKT_VERSION=${KUBE_RKT_VERSION:-0.5.5}
 

cluster/gce/config-test.sh

@@ -35,11 +35,13 @@ KUBE_APISERVER_REQUEST_TIMEOUT=300
 PREEMPTIBLE_NODE=${PREEMPTIBLE_NODE:-false}
 PREEMPTIBLE_MASTER=${PREEMPTIBLE_MASTER:-false}
 
-OS_DISTRIBUTION=${KUBE_OS_DISTRIBUTION:-debian}
-MASTER_IMAGE=${KUBE_GCE_MASTER_IMAGE:-container-vm-v20160321}
+OS_DISTRIBUTION=${KUBE_OS_DISTRIBUTION:-gci}
+# For GCI, leaving it blank will auto-select the latest GCI image on the `dev`
+# channel.
+MASTER_IMAGE=${KUBE_GCE_MASTER_IMAGE:-}
 MASTER_IMAGE_PROJECT=${KUBE_GCE_MASTER_PROJECT:-google-containers}
-NODE_IMAGE=${KUBE_GCE_NODE_IMAGE:-"${MASTER_IMAGE}"}
-NODE_IMAGE_PROJECT=${KUBE_GCE_NODE_PROJECT:-"${MASTER_IMAGE_PROJECT}"}
+NODE_IMAGE=${KUBE_GCE_NODE_IMAGE:-container-vm-v20160321}
+NODE_IMAGE_PROJECT=${KUBE_GCE_NODE_PROJECT:-google-containers}
 CONTAINER_RUNTIME=${KUBE_CONTAINER_RUNTIME:-docker}
 RKT_VERSION=${KUBE_RKT_VERSION:-0.5.5}
 

cluster/gce/util.sh

@@ -35,11 +35,11 @@ if [[ "${OS_DISTRIBUTION}" == "gci" ]]; then
   # Otherwise, we respect whatever set by the user.
   gci_images=( $(gcloud compute images list --project google-containers \
       --regexp='gci-dev.*' --format='value(name)') )
-  if [[ -z "${KUBE_GCE_MASTER_IMAGE:-}" ]]; then
+  if [[ -z "${MASTER_IMAGE:-}" ]]; then
     MASTER_IMAGE="${gci_images[0]}"
     MASTER_IMAGE_PROJECT="google-containers"
   fi
-  if [[ -z "${KUBE_GCE_NODE_IMAGE:-}" ]]; then
+  if [[ -z "${NODE_IMAGE:-}" ]]; then
     NODE_IMAGE="${gci_images[0]}"
     NODE_IMAGE_PROJECT="google-containers"
   fi

hack/ginkgo-e2e.sh

@@ -105,7 +105,7 @@ export PATH=$(dirname "${e2e_test}"):"${PATH}"
   --repo-root="${KUBE_ROOT}" \
   --node-instance-group="${NODE_INSTANCE_GROUP:-}" \
   --prefix="${KUBE_GCE_INSTANCE_PREFIX:-e2e}" \
-  ${KUBE_OS_DISTRIBUTION:+"--os-distro=${KUBE_OS_DISTRIBUTION}"} \
+  ${OS_DISTRIBUTION:+"--os-distro=${OS_DISTRIBUTION}"} \
   ${NUM_NODES:+"--num-nodes=${NUM_NODES}"} \
   ${E2E_CLEAN_START:+"--clean-start=true"} \
   ${E2E_MIN_STARTUP_PODS:+"--minStartupPods=${E2E_MIN_STARTUP_PODS}"} \

hack/verify-flags/exceptions.txt

@@ -8,6 +8,7 @@ cluster/aws/templates/configure-vm-aws.sh:  env-to-grains "hostname_override"
 cluster/aws/templates/configure-vm-aws.sh:  env-to-grains "runtime_config"
 cluster/aws/templates/configure-vm-aws.sh:  kubelet_api_servers: '${KUBELET_APISERVER}'
 cluster/centos/util.sh:  local node_ip=${node#*@}
+cluster/gce/config-default.sh:# reloads <os_distro>/helper.sh in the gap between when the master is created
 cluster/gce/configure-vm.sh:  advertise_address: '${EXTERNAL_IP}'
 cluster/gce/configure-vm.sh:  api_servers: '${KUBERNETES_MASTER_NAME}'
 cluster/gce/configure-vm.sh:  cloud_config: ${CLOUD_CONFIG}