Add etcd-only/control-plane-only server test

scripts/test-helpers

@@ -430,7 +430,7 @@ provision-cluster() {
         provision-server
         timeout --foreground 120s bash -c "wait-for-kubeconfig $i"
     done
-    export KUBECONFIG=$TEST_DIR/servers/1/kubeconfig.yaml
+    export KUBECONFIG=$TEST_DIR/servers/${KUBECONFIG_SERVER:-1}/kubeconfig.yaml
 
     if [ $NUM_AGENTS -gt 0 ]; then
         for _ in $(seq 1 $NUM_AGENTS); do

scripts/test-run-etcd

@@ -38,6 +38,17 @@ LABEL="ETCD-JOIN-BASIC" SERVER_ARGS="" run-test
 # --- create a basic cluster to test joining a managed etcd cluster with --agent-token set
 LABEL="ETCD-JOIN-AGENTTOKEN" SERVER_ARGS="--agent-token ${RANDOM}${RANDOM}${RANDOM}" run-test
 
+# --- create a cluster with one etcd-only server, one control-plane-only server, and one agent
+server-post-hook() {
+  if [ $1 -eq 1 ]; then
+    local url=$(cat $TEST_DIR/servers/1/metadata/url)
+    export SERVER_ARGS="${SERVER_ARGS} --server $url"
+  fi
+}
+export -f server-post-hook
+LABEL="ETCD-SPLIT-ROLE" NUM_AGENTS=1 KUBECONFIG_SERVER=2 SERVER_1_ARGS="--cluster-init --disable-apiserver --disable-controller-manager --disable-scheduler" SERVER_2_ARGS="--disable-etcd" run-test
+
+
 # The following tests deploy clusters of mixed versions. The traefik helm chart may not deploy
 # correctly until all servers have been upgraded to the same release, so don't wait for it.
 all_services=(