Allow setting KUBERNETES_NODE_ARCH to download node binaries

cluster/get-kube-binaries.sh

@@ -161,9 +161,9 @@ DOWNLOAD_URL_PREFIX="${KUBERNETES_RELEASE_URL}/${KUBE_VERSION}"
 SERVER_PLATFORM="linux"
 SERVER_ARCH="${KUBERNETES_SERVER_ARCH:-amd64}"
 SERVER_TAR="kubernetes-server-${SERVER_PLATFORM}-${SERVER_ARCH}.tar.gz"
-if [[ -n "${KUBERNETES_NODE_PLATFORM-}" ]]; then
-  NODE_PLATFORM="${KUBERNETES_NODE_PLATFORM}"
-  NODE_ARCH="${KUBERNETES_NODE_ARCH:-amd64}"
+if [[ -n "${KUBERNETES_NODE_PLATFORM-}" || -n "${KUBERNETES_NODE_ARCH-}" ]]; then
+  NODE_PLATFORM="${KUBERNETES_NODE_PLATFORM:${SERVER_PLATFORM}}"
+  NODE_ARCH="${KUBERNETES_NODE_ARCH:${SERVER_ARCH}}"
   NODE_TAR="kubernetes-node-${NODE_PLATFORM}-${NODE_ARCH}.tar.gz"
 fi
 

cluster/get-kube.sh

@@ -38,12 +38,18 @@
 #    * arm64
 #
 #  Set KUBERNETES_NODE_PLATFORM to choose the platform for which to download
-#  the node binaries. If not set (the default) no node binaries will be
-#  downloaded. The options are:
+#  the node binaries. If none of KUBERNETES_NODE_PLATFORM and
+#  KUBERNETES_NODE_ARCH is set, no node binaries will be downloaded. If only
+#  one of the two is set, the other will be defaulted to the
+#  KUBERNETES_SERVER_PLATFORM/ARCH.
 #    * linux
 #    * windows
 #
-#  Set KUBERNETES_NODE_ARCH to choose the node architecture to download:
+#  Set KUBERNETES_NODE_ARCH to choose the node architecture to download the
+#  node binaries. If none of KUBERNETES_NODE_PLATFORM and
+#  KUBERNETES_NODE_ARCH is set, no node binaries will be downloaded. If only
+#  one of the two is set, the other will be defaulted to the
+#  KUBERNETES_SERVER_PLATFORM/ARCH.
 #    * amd64 [default]
 #    * arm
 #    * arm64