build large clusters gradually

Author: jackfrancis

scripts/ci-entrypoint.sh

@@ -31,6 +31,7 @@ KUSTOMIZE="${REPO_ROOT}/hack/tools/bin/kustomize"
 make --directory="${REPO_ROOT}" "${KUBECTL##*/}" "${HELM##*/}" "${KIND##*/}" "${KUSTOMIZE##*/}"
 KIND_CLUSTER_NAME="${KIND_CLUSTER_NAME:-capz}"
 WORKER_MACHINE_COUNT="${WORKER_MACHINE_COUNT:-2}"
+EXTRA_NODES="${EXTRA_NODES:-0}"
 export KIND_CLUSTER_NAME
 # export the variables so they are available in bash -c wait_for_nodes below
 export KUBECTL
@@ -214,6 +215,22 @@ wait_for_pods() {
     done
 }
 
+# wait_for_extra_nodes accommodates building large clusters gradually
+wait_for_extra_nodes() {
+    local existing_nodes="${WORKER_MACHINE_COUNT}"
+    local remaining_extra_nodes="${EXTRA_NODES}"
+    while [[ "${remaining_extra_nodes}" -gt 10 ]]; do
+        NEW_REPLICA_COUNT=$((existing_nodes + 10))
+        "${KUBECTL}" --kubeconfig "${REPO_ROOT}/${KIND_CLUSTER_NAME}.kubeconfig" scale machinedeployment/"${CLUSTER_NAME}"-md-0 --replicas="${NEW_REPLICA_COUNT}"
+        sleep 120
+        existing_nodes=$((existing_nodes + 10))
+        remaining_extra_nodes=$((remaining_extra_nodes - 10))
+    done
+    NEW_REPLICA_COUNT=$((existing_nodes + remaining_extra_nodes))
+    "${KUBECTL}" --kubeconfig "${REPO_ROOT}/${KIND_CLUSTER_NAME}.kubeconfig" scale machinedeployment/"${CLUSTER_NAME}"-md-0 --replicas="${NEW_REPLICA_COUNT}"
+    sleep 120
+}
+
 install_addons() {
     export -f copy_kubeadm_config_map wait_for_copy_kubeadm_config_map
     timeout --foreground 600 bash -c wait_for_copy_kubeadm_config_map
@@ -224,6 +241,8 @@ install_addons() {
     timeout --foreground 1800 bash -c wait_for_nodes
     export -f wait_for_pods
     timeout --foreground 1800 bash -c wait_for_pods
+    export -f wait_for_extra_nodes
+    timeout --foreground 10800 bash -c wait_for_pods
 }
 
 copy_secret() {