diff --git a/cluster/centos/.gitignore b/cluster/centos/.gitignore
index c97ce235be4..96c52004b2a 100644
--- a/cluster/centos/.gitignore
+++ b/cluster/centos/.gitignore
@@ -1,4 +1,5 @@
 binaries
+ca-cert
 
 master/bin/etcd
 master/bin/etcdctl
diff --git a/cluster/centos/config-default.sh b/cluster/centos/config-default.sh
index 61d823f5728..d5409f1ddc0 100755
--- a/cluster/centos/config-default.sh
+++ b/cluster/centos/config-default.sh
@@ -14,24 +14,90 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+readonly root=$(dirname "${BASH_SOURCE}")
+
 ## Contains configuration values for the CentOS cluster
 # The user should have sudo privilege
 export MASTER=${MASTER:-"centos@172.10.0.11"}
 export MASTER_IP=${MASTER#*@}
 
+# Define all your master nodes,
+# And separated with blank space like <user_1@ip_1> <user_2@ip_2> <user_3@ip_3>.
+# The user should have sudo privilege
+export MASTERS="${MASTERS:-$MASTER}"
+
+# length-of <arg0>
+# Get the length of specific arg0, could be a space-separate string or array.
+function length-of() {
+  local len=0
+  for part in $1; do
+    let ++len
+  done
+  echo $len
+}
+# Number of nodes in your cluster.
+export NUM_MASTERS="${NUM_MASTERS:-$(length-of "$MASTERS")}"
+
+# Get default master advertise address: first master node.
+function default-advertise-address() {
+  # get the first master node
+  local masters_array=(${MASTERS})
+  local master=${masters_array[0]}
+  echo ${master#*@}
+}
+
+# Define advertise address of masters, could be a load balancer address.
+# If not provided, the default is ip of first master node.
+export MASTER_ADVERTISE_ADDRESS="${MASTER_ADVERTISE_ADDRESS:-$(default-advertise-address)}"
+export MASTER_ADVERTISE_IP="${MASTER_ADVERTISE_IP:-$(getent hosts "${MASTER_ADVERTISE_ADDRESS}" | awk '{print $1; exit}')}"
+
 # Define all your minion nodes,
 # And separated with blank space like <user_1@ip_1> <user_2@ip_2> <user_3@ip_3>.
 # The user should have sudo privilege
-export NODES=${NODES:-"centos@172.10.0.12 centos@172.10.0.13"}
+export NODES="${NODES:-"centos@172.10.0.12 centos@172.10.0.13"}"
 
 # Number of nodes in your cluster.
-export NUM_NODES=${NUM_NODES:-2}
+export NUM_NODES="${NUM_NODES:-$(length-of "$NODES")}"
 
 # Should be removed when NUM_NODES is deprecated in validate-cluster.sh
-export NUM_NODES=${NUM_NODES}
+export NUM_NODES="${NUM_NODES}"
 
 # By default, the cluster will use the etcd installed on master.
-export ETCD_SERVERS=${ETCD_SERVERS:-"http://$MASTER_IP:2379"}
+function concat-etcd-servers() {
+  local etcd_servers=""
+  for master in ${MASTERS}; do
+    local master_ip=${master#*@}
+    local prefix=""
+    if [ -n "$etcd_servers" ]; then
+      prefix="${etcd_servers},"
+    fi
+    etcd_servers="${prefix}http://${master_ip}:2379"
+  done
+
+  echo "$etcd_servers"
+}
+export ETCD_SERVERS="$(concat-etcd-servers)"
+
+# By default, etcd cluster will use runtime configuration
+#   https://coreos.com/etcd/docs/latest/v2/runtime-configuration.html
+# Get etc initial cluster and store in ETCD_INITIAL_CLUSTER
+function concat-etcd-initial-cluster() {
+  local etcd_initial_cluster=""
+  local num_infra=0
+  for master in ${MASTERS}; do
+    local master_ip="${master#*@}"
+    if [ -n "$etcd_initial_cluster" ]; then
+      etcd_initial_cluster+=","
+    fi
+    etcd_initial_cluster+="infra${num_infra}=http://${master_ip}:2380"
+    let ++num_infra
+  done
+
+  echo "$etcd_initial_cluster"
+}
+export ETCD_INITIAL_CLUSTER="$(concat-etcd-initial-cluster)"
+
+export CERT_DIR="${CERT_DIR:-$(cd "${root}/ca-cert" && pwd)}"
 
 # define the IP range used for service cluster IPs.
 # according to rfc 1918 ref: https://tools.ietf.org/html/rfc1918 choose a private ip range here.
@@ -55,8 +121,10 @@ export ADMISSION_CONTROL=NamespaceLifecycle,LimitRanger,ServiceAccount,ResourceQ
 
 # Extra options to set on the Docker command line.
 # This is useful for setting --insecure-registry for local registries.
-export DOCKER_OPTS=${DOCKER_OPTS:-""} 
+export DOCKER_OPTS=${DOCKER_OPTS:-""}
 
 
 # Timeouts for process checking on master and minion
 export PROCESS_CHECK_TIMEOUT=${PROCESS_CHECK_TIMEOUT:-180} # seconds.
+
+unset -f default-advertise-address concat-etcd-servers length-of concat-etcd-initial-cluster
diff --git a/cluster/centos/master/scripts/apiserver.sh b/cluster/centos/master/scripts/apiserver.sh
index 0479d7b28bd..2db77443656 100755
--- a/cluster/centos/master/scripts/apiserver.sh
+++ b/cluster/centos/master/scripts/apiserver.sh
@@ -32,7 +32,7 @@ KUBE_LOG_LEVEL="--v=4"
 KUBE_ETCD_SERVERS="--etcd-servers=${ETCD_SERVERS}"
 
 # --insecure-bind-address=127.0.0.1: The IP address on which to serve the --insecure-port.
-KUBE_API_ADDRESS="--insecure-bind-address=${MASTER_ADDRESS}"
+KUBE_API_ADDRESS="--insecure-bind-address=0.0.0.0"
 
 # --insecure-port=8080: The port on which to serve unsecured, unauthenticated access.
 KUBE_API_PORT="--insecure-port=8080"
diff --git a/cluster/centos/master/scripts/controller-manager.sh b/cluster/centos/master/scripts/controller-manager.sh
index 6b950e5bf27..3025d06fda4 100755
--- a/cluster/centos/master/scripts/controller-manager.sh
+++ b/cluster/centos/master/scripts/controller-manager.sh
@@ -29,13 +29,17 @@ KUBE_CONTROLLER_MANAGER_ROOT_CA_FILE="--root-ca-file=/srv/kubernetes/ca.crt"
 # --service-account-private-key-file="": Filename containing a PEM-encoded private
 # RSA key used to sign service account tokens.
 KUBE_CONTROLLER_MANAGER_SERVICE_ACCOUNT_PRIVATE_KEY_FILE="--service-account-private-key-file=/srv/kubernetes/server.key"
+
+# --leader-elect
+KUBE_LEADER_ELECT="--leader-elect"
 EOF
 
 KUBE_CONTROLLER_MANAGER_OPTS="  \${KUBE_LOGTOSTDERR} \\
                                 \${KUBE_LOG_LEVEL}   \\
                                 \${KUBE_MASTER}      \\
                                 \${KUBE_CONTROLLER_MANAGER_ROOT_CA_FILE} \\
-                                \${KUBE_CONTROLLER_MANAGER_SERVICE_ACCOUNT_PRIVATE_KEY_FILE}"
+                                \${KUBE_CONTROLLER_MANAGER_SERVICE_ACCOUNT_PRIVATE_KEY_FILE}\\
+                                \${KUBE_LEADER_ELECT}"
 
 cat <<EOF >/usr/lib/systemd/system/kube-controller-manager.service
 [Unit]
diff --git a/cluster/centos/master/scripts/etcd.sh b/cluster/centos/master/scripts/etcd.sh
index c6d11a4ee70..824b639396c 100755
--- a/cluster/centos/master/scripts/etcd.sh
+++ b/cluster/centos/master/scripts/etcd.sh
@@ -17,30 +17,34 @@
 ## Create etcd.conf, etcd.service, and start etcd service.
 
 
-etcd_data_dir=/var/lib/etcd/
+etcd_data_dir=/var/lib/etcd
 mkdir -p ${etcd_data_dir}
 
+ETCD_NAME=${1:-"default"}
+ETCD_LISTEN_IP=${2:-"0.0.0.0"}
+ETCD_INITIAL_CLUSTER=${3:-}
+
 cat <<EOF >/opt/kubernetes/cfg/etcd.conf
 # [member]
-ETCD_NAME=default
+ETCD_NAME="${ETCD_NAME}"
 ETCD_DATA_DIR="${etcd_data_dir}/default.etcd"
 #ETCD_SNAPSHOT_COUNTER="10000"
 #ETCD_HEARTBEAT_INTERVAL="100"
 #ETCD_ELECTION_TIMEOUT="1000"
-#ETCD_LISTEN_PEER_URLS="http://localhost:2380,http://localhost:7001"
-ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379"
+ETCD_LISTEN_PEER_URLS="http://${ETCD_LISTEN_IP}:2380"
+ETCD_LISTEN_CLIENT_URLS="http://${ETCD_LISTEN_IP}:2379,http://127.0.0.1:2379"
 #ETCD_MAX_SNAPSHOTS="5"
 #ETCD_MAX_WALS="5"
 #ETCD_CORS=""
 #
 #[cluster]
-#ETCD_INITIAL_ADVERTISE_PEER_URLS="http://localhost:2380,http://localhost:7001"
+ETCD_INITIAL_ADVERTISE_PEER_URLS="http://${ETCD_LISTEN_IP}:2380"
 # if you use different ETCD_NAME (e.g. test),
 # set ETCD_INITIAL_CLUSTER value for this name, i.e. "test=http://..."
-#ETCD_INITIAL_CLUSTER="default=http://localhost:2380,default=http://localhost:7001"
-#ETCD_INITIAL_CLUSTER_STATE="new"
-#ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
-ETCD_ADVERTISE_CLIENT_URLS="http://localhost:2379"
+ETCD_INITIAL_CLUSTER="${ETCD_INITIAL_CLUSTER}"
+ETCD_INITIAL_CLUSTER_STATE="new"
+ETCD_INITIAL_CLUSTER_TOKEN="k8s-etcd-cluster"
+ETCD_ADVERTISE_CLIENT_URLS="http://${ETCD_LISTEN_IP}:2379"
 #ETCD_DISCOVERY=""
 #ETCD_DISCOVERY_SRV=""
 #ETCD_DISCOVERY_FALLBACK="proxy"
diff --git a/cluster/centos/master/scripts/post-etcd.sh b/cluster/centos/master/scripts/post-etcd.sh
new file mode 100644
index 00000000000..be18590755c
--- /dev/null
+++ b/cluster/centos/master/scripts/post-etcd.sh
@@ -0,0 +1,23 @@
+#!/bin/bash
+
+# Copyright 2014 The Kubernetes Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+## Set initial-cluster-state to existing, and restart etcd service.
+
+sed -i 's/ETCD_INITIAL_CLUSTER_STATE="new"/ETCD_INITIAL_CLUSTER_STATE="existing"/' /opt/kubernetes/cfg/etcd.conf
+
+systemctl daemon-reload
+systemctl enable etcd
+systemctl restart etcd
diff --git a/cluster/centos/master/scripts/scheduler.sh b/cluster/centos/master/scripts/scheduler.sh
index bebb101cd10..1a68d71938a 100755
--- a/cluster/centos/master/scripts/scheduler.sh
+++ b/cluster/centos/master/scripts/scheduler.sh
@@ -29,6 +29,9 @@ KUBE_LOG_LEVEL="--v=4"
 
 KUBE_MASTER="--master=${MASTER_ADDRESS}:8080"
 
+# --leader-elect
+KUBE_LEADER_ELECT="--leader-elect"
+
 # Add your own!
 KUBE_SCHEDULER_ARGS=""
 
@@ -37,6 +40,7 @@ EOF
 KUBE_SCHEDULER_OPTS="   \${KUBE_LOGTOSTDERR}     \\
                         \${KUBE_LOG_LEVEL}       \\
                         \${KUBE_MASTER}          \\
+                        \${KUBE_LEADER_ELECT}    \\
                         \${KUBE_SCHEDULER_ARGS}"
 
 cat <<EOF >/usr/lib/systemd/system/kube-scheduler.service
diff --git a/cluster/centos/util.sh b/cluster/centos/util.sh
index 48c6a7ee937..c92582493c8 100755
--- a/cluster/centos/util.sh
+++ b/cluster/centos/util.sh
@@ -35,12 +35,16 @@ KUBECTL_PATH=${KUBE_ROOT}/cluster/centos/binaries/kubectl
 KUBE_TEMP="~/kube_temp"
 
 
-# Must ensure that the following ENV vars are set
-function detect-master() {
-  KUBE_MASTER=$MASTER
-  KUBE_MASTER_IP=${MASTER#*@}
-  echo "KUBE_MASTER_IP: ${KUBE_MASTER_IP}" 1>&2
-  echo "KUBE_MASTER: ${MASTER}" 1>&2
+# Get master IP addresses and store in KUBE_MASTER_IP_ADDRESSES[]
+# Must ensure that the following ENV vars are set:
+#   MASTERS
+function detect-masters() {
+  KUBE_MASTER_IP_ADDRESSES=()
+  for master in ${MASTERS}; do
+    KUBE_MASTER_IP_ADDRESSES+=("${master#*@}")
+  done
+  echo "KUBE_MASTERS: ${MASTERS}" 1>&2
+  echo "KUBE_MASTER_IP_ADDRESSES: [${KUBE_MASTER_IP_ADDRESSES[*]}]" 1>&2
 }
 
 # Get node IP addresses and store in KUBE_NODE_IP_ADDRESSES[]
@@ -99,7 +103,9 @@ function validate-cluster() {
   set +e
   "${KUBE_ROOT}/cluster/validate-cluster.sh"
   if [[ "$?" -ne "0" ]]; then
-    troubleshoot-master
+    for master in ${MASTERS}; do
+      troubleshoot-master ${master}
+    done
     for node in ${NODES}; do
       troubleshoot-node ${node}
     done
@@ -110,17 +116,27 @@ function validate-cluster() {
 
 # Instantiate a kubernetes cluster
 function kube-up() {
-  provision-master
+  make-ca-cert
 
-  for node in ${NODES}; do
-    provision-node ${node}
+  local num_infra=0
+  for master in ${MASTERS}; do
+    provision-master "${master}" "infra${num_infra}"
+    let ++num_infra
   done
 
-  detect-master
+  for master in ${MASTERS}; do
+    post-provision-master "${master}"
+  done
+
+  for node in ${NODES}; do
+    provision-node "${node}"
+  done
+
+  detect-masters
 
   # set CONTEXT and KUBE_SERVER values for create-kubeconfig() and get-password()
   export CONTEXT="centos"
-  export KUBE_SERVER="http://${KUBE_MASTER_IP}:8080"
+  export KUBE_SERVER="http://${MASTER_ADVERTISE_ADDRESS}:8080"
   source "${KUBE_ROOT}/cluster/common.sh"
 
   # set kubernetes user and password
@@ -130,7 +146,10 @@ function kube-up() {
 
 # Delete a kubernetes cluster
 function kube-down() {
-  tear-down-master
+  for master in ${MASTERS}; do
+    tear-down-master ${master}
+  done
+
   for node in ${NODES}; do
     tear-down-node ${node}
   done
@@ -138,14 +157,14 @@ function kube-down() {
 
 function troubleshoot-master() {
   # Troubleshooting on master if all required daemons are active.
-  echo "[INFO] Troubleshooting on master ${MASTER}"
+  echo "[INFO] Troubleshooting on master $1"
   local -a required_daemon=("kube-apiserver" "kube-controller-manager" "kube-scheduler")
   local daemon
   local daemon_status
   printf "%-24s %-10s \n" "PROCESS" "STATUS"
   for daemon in "${required_daemon[@]}"; do
     local rc=0
-    kube-ssh "${MASTER}" "sudo systemctl is-active ${daemon}" >/dev/null 2>&1 || rc="$?"
+    kube-ssh "${1}" "sudo systemctl is-active ${daemon}" >/dev/null 2>&1 || rc="$?"
     if [[ "${rc}" -ne "0" ]]; then
       daemon_status="inactive"
     else
@@ -178,19 +197,19 @@ function troubleshoot-node() {
 
 # Clean up on master
 function tear-down-master() {
-echo "[INFO] tear-down-master on ${MASTER}"
+echo "[INFO] tear-down-master on $1"
   for service_name in etcd kube-apiserver kube-controller-manager kube-scheduler ; do
       service_file="/usr/lib/systemd/system/${service_name}.service"
-      kube-ssh "$MASTER" " \
+      kube-ssh "$1" " \
         if [[ -f $service_file ]]; then \
           sudo systemctl stop $service_name; \
           sudo systemctl disable $service_name; \
           sudo rm -f $service_file; \
         fi"
   done
-  kube-ssh "${MASTER}" "sudo rm -rf /opt/kubernetes"
-  kube-ssh "${MASTER}" "sudo rm -rf ${KUBE_TEMP}"
-  kube-ssh "${MASTER}" "sudo rm -rf /var/lib/etcd"
+  kube-ssh "${1}" "sudo rm -rf /opt/kubernetes"
+  kube-ssh "${1}" "sudo rm -rf ${KUBE_TEMP}"
+  kube-ssh "${1}" "sudo rm -rf /var/lib/etcd"
 }
 
 # Clean up on node
@@ -210,46 +229,69 @@ echo "[INFO] tear-down-node on $1"
   kube-ssh "$1" "sudo rm -rf ${KUBE_TEMP}"
 }
 
+# Generate the CA certificates for k8s components
+function make-ca-cert() {
+  echo "[INFO] make-ca-cert"
+  bash "${ROOT}/../saltbase/salt/generate-cert/make-ca-cert.sh" "${MASTER_ADVERTISE_IP}" "IP:${MASTER_ADVERTISE_IP},IP:${SERVICE_CLUSTER_IP_RANGE%.*}.1,DNS:kubernetes,DNS:kubernetes.default,DNS:kubernetes.default.svc,DNS:kubernetes.default.svc.cluster.local"
+}
+
 # Provision master
 #
 # Assumed vars:
-#   MASTER
+#   $1 (master)
 #   KUBE_TEMP
 #   ETCD_SERVERS
+#   ETCD_INITIAL_CLUSTER
 #   SERVICE_CLUSTER_IP_RANGE
+#   MASTER_ADVERTISE_ADDRESS
 function provision-master() {
-  echo "[INFO] Provision master on ${MASTER}"
-  local master_ip=${MASTER#*@}
-  ensure-setup-dir ${MASTER}
+  echo "[INFO] Provision master on $1"
+  local master="$1"
+  local master_ip="${master#*@}"
+  local etcd_name="$2"
+  ensure-setup-dir "${master}"
 
-  # scp -r ${SSH_OPTS} master config-default.sh copy-files.sh util.sh "${MASTER}:${KUBE_TEMP}"
-  kube-scp ${MASTER} "${ROOT}/../saltbase/salt/generate-cert/make-ca-cert.sh ${ROOT}/binaries/master ${ROOT}/master ${ROOT}/config-default.sh ${ROOT}/util.sh" "${KUBE_TEMP}"
-  kube-ssh "${MASTER}" " \
-    rm -rf /opt/kubernetes/bin; \
+  kube-scp "${master}" "${ROOT}/ca-cert ${ROOT}/binaries/master ${ROOT}/master ${ROOT}/config-default.sh ${ROOT}/util.sh" "${KUBE_TEMP}"
+  kube-ssh "${master}" " \
+    sudo rm -rf /opt/kubernetes/bin; \
     sudo cp -r ${KUBE_TEMP}/master/bin /opt/kubernetes; \
+    sudo mkdir -p /srv/kubernetes; sudo cp -f ${KUBE_TEMP}/ca-cert/* /srv/kubernetes; \
     sudo chmod -R +x /opt/kubernetes/bin; \
-    sudo ln -s /opt/kubernetes/bin/* /usr/local/bin/; \
-    sudo bash ${KUBE_TEMP}/make-ca-cert.sh ${master_ip} IP:${master_ip},IP:${SERVICE_CLUSTER_IP_RANGE%.*}.1,DNS:kubernetes,DNS:kubernetes.default,DNS:kubernetes.default.svc,DNS:kubernetes.default.svc.cluster.local; \
-    sudo bash ${KUBE_TEMP}/master/scripts/etcd.sh; \
+    sudo ln -sf /opt/kubernetes/bin/* /usr/local/bin/; \
+    sudo bash ${KUBE_TEMP}/master/scripts/etcd.sh ${etcd_name} ${master_ip} ${ETCD_INITIAL_CLUSTER}; \
     sudo bash ${KUBE_TEMP}/master/scripts/apiserver.sh ${master_ip} ${ETCD_SERVERS} ${SERVICE_CLUSTER_IP_RANGE} ${ADMISSION_CONTROL}; \
-    sudo bash ${KUBE_TEMP}/master/scripts/controller-manager.sh ${master_ip}; \
-    sudo bash ${KUBE_TEMP}/master/scripts/flannel.sh ${ETCD_SERVERS} ${FLANNEL_NET}; \
-    sudo bash ${KUBE_TEMP}/master/scripts/scheduler.sh ${master_ip}"
+    sudo bash ${KUBE_TEMP}/master/scripts/controller-manager.sh ${MASTER_ADVERTISE_ADDRESS}; \
+    sudo bash ${KUBE_TEMP}/master/scripts/scheduler.sh ${MASTER_ADVERTISE_ADDRESS}"
 }
 
+# Post-provision master, run after all masters were provisioned
+#
+# Assumed vars:
+#   $1 (master)
+#   KUBE_TEMP
+#   ETCD_SERVERS
+#   FLANNEL_NET
+function post-provision-master() {
+  echo "[INFO] Post provision master on $1"
+  local master=$1
+  kube-ssh "${master}" " \
+    sudo bash ${KUBE_TEMP}/master/scripts/flannel.sh ${ETCD_SERVERS} ${FLANNEL_NET}; \
+    sudo bash ${KUBE_TEMP}/master/scripts/post-etcd.sh"
+}
 
 # Provision node
 #
 # Assumed vars:
 #   $1 (node)
-#   MASTER
 #   KUBE_TEMP
 #   ETCD_SERVERS
 #   FLANNEL_NET
+#   MASTER_ADVERTISE_ADDRESS
 #   DOCKER_OPTS
+#   DNS_SERVER_IP
+#   DNS_DOMAIN
 function provision-node() {
   echo "[INFO] Provision node on $1"
-  local master_ip=${MASTER#*@}
   local node=$1
   local node_ip=${node#*@}
   local dns_ip=${DNS_SERVER_IP#*@}
@@ -264,8 +306,8 @@ function provision-node() {
     sudo ln -s /opt/kubernetes/bin/* /usr/local/bin/; \
     sudo bash ${KUBE_TEMP}/node/scripts/flannel.sh ${ETCD_SERVERS} ${FLANNEL_NET}; \
     sudo bash ${KUBE_TEMP}/node/scripts/docker.sh \"${DOCKER_OPTS}\"; \
-    sudo bash ${KUBE_TEMP}/node/scripts/kubelet.sh ${master_ip} ${node_ip} ${dns_ip} ${dns_domain}; \
-    sudo bash ${KUBE_TEMP}/node/scripts/proxy.sh ${master_ip}"
+    sudo bash ${KUBE_TEMP}/node/scripts/kubelet.sh ${MASTER_ADVERTISE_ADDRESS} ${node_ip} ${dns_ip} ${dns_domain}; \
+    sudo bash ${KUBE_TEMP}/node/scripts/proxy.sh ${MASTER_ADVERTISE_ADDRESS}"
 }
 
 # Create dirs that'll be used during setup on target machine.
diff --git a/hack/verify-flags/exceptions.txt b/hack/verify-flags/exceptions.txt
index 7c9dc1de671..b7924f25ffd 100644
--- a/hack/verify-flags/exceptions.txt
+++ b/hack/verify-flags/exceptions.txt
@@ -5,6 +5,8 @@ cluster/aws/templates/configure-vm-aws.sh:  api_servers: '${API_SERVERS}'
 cluster/aws/templates/configure-vm-aws.sh:  env-to-grains "hostname_override"
 cluster/aws/templates/configure-vm-aws.sh:  env-to-grains "runtime_config"
 cluster/aws/templates/configure-vm-aws.sh:  kubelet_api_servers: '${KUBELET_APISERVER}'
+cluster/centos/config-default.sh:    etcd_servers="${prefix}http://${master_ip}:2379"
+cluster/centos/config-default.sh:  local etcd_servers=""
 cluster/centos/util.sh:  local node_ip=${node#*@}
 cluster/gce/configure-vm.sh:  advertise_address: '${EXTERNAL_IP}'
 cluster/gce/configure-vm.sh:  api_servers: '${KUBERNETES_MASTER_NAME}'