Merge pull request #2289 from AndrewSirenko/single-az-warn

Fast-fail `make e2e/single-az` if cluster has nodes in multiple AZs

hack/e2e/run.sh

@@ -41,6 +41,22 @@ else
   exit 1
 fi
 
+# Fail single-az tests early if we know cluster is multi-az.
+IGNORE_SINGLE_AZ_ERR=${IGNORE_SINGLE_AZ_ERR:="false"}
+if [[ $IGNORE_SINGLE_AZ_ERR != "true" && "$GINKGO_FOCUS" =~ "single-az" ]]; then
+  # Get unique AZs of non-control-plane nodes
+  azs=$(kubectl get nodes \
+    --kubeconfig "${KUBECONFIG}" \
+    --selector '!node-role.kubernetes.io/control-plane' \
+    -o jsonpath='{.items[*].metadata.labels.topology\.kubernetes\.io/zone}' | tr " " "\n" | sort -u)
+
+  # Check if there's exactly one AZ and it matches $AWS_AVAILABILITY_ZONES
+  if [[ $(echo "$azs" | wc -w) -gt 1 ]] || [[ "$azs" != "$AWS_AVAILABILITY_ZONES" ]]; then
+    loudecho "ERROR. single-az tests require all worker nodes to be in a single availability zone (AZ) that matches env var \$AWS_AVAILABILITY_ZONES (Currently set as \"$AWS_AVAILABILITY_ZONES\"). Please delete nodes in other AZs. If you want to bypass this error, set env var IGNORE_SINGLE_AZ_ERR='true'"
+    exit 1
+  fi
+fi
+
 if [[ "$WINDOWS" == true ]]; then
   NODE_OS_DISTRO="windows"
 else