diff --git a/cluster/libvirt-coreos/config-default.sh b/cluster/libvirt-coreos/config-default.sh
index cce5c06c689..76b9c9aedde 100644
--- a/cluster/libvirt-coreos/config-default.sh
+++ b/cluster/libvirt-coreos/config-default.sh
@@ -19,3 +19,31 @@
 # Number of minions in the cluster
 NUM_MINIONS=${NUM_MINIONS:-3}
 export NUM_MINIONS
+
+# The IP of the master
+export MASTER_IP="192.168.10.1"
+
+export INSTANCE_PREFIX=kubernetes
+export MASTER_NAME="${INSTANCE_PREFIX}-master"
+
+# Map out the IPs, names and container subnets of each minion
+export MINION_IP_BASE="192.168.10."
+MINION_CONTAINER_SUBNET_BASE="10.10"
+MASTER_CONTAINER_NETMASK="255.255.255.0"
+MASTER_CONTAINER_ADDR="${MINION_CONTAINER_SUBNET_BASE}.0.1"
+MASTER_CONTAINER_SUBNET="${MINION_CONTAINER_SUBNET_BASE}.0.1/24"
+CONTAINER_SUBNET="${MINION_CONTAINER_SUBNET_BASE}.0.0/16"
+if [[ "$NUM_MINIONS" -gt 253 ]]; then
+  echo "ERROR: Because of how IPs are allocated in ${BASH_SOURCE}, you cannot create more than 253 minions"
+  exit 1
+fi
+for ((i=0; i < NUM_MINIONS; i++)) do
+  MINION_IPS[$i]="${MINION_IP_BASE}$((i+2))"
+  MINION_NAMES[$i]="${INSTANCE_PREFIX}-minion-$((i+1))"
+  MINION_CONTAINER_SUBNETS[$i]="${MINION_CONTAINER_SUBNET_BASE}.$((i+1)).1/24"
+  MINION_CONTAINER_ADDRS[$i]="${MINION_CONTAINER_SUBNET_BASE}.$((i+1)).1"
+  MINION_CONTAINER_NETMASKS[$i]="255.255.255.0"
+done
+MINION_CONTAINER_SUBNETS[$NUM_MINIONS]=$MASTER_CONTAINER_SUBNET
+
+PORTAL_NET=10.11.0.0/16
diff --git a/cluster/libvirt-coreos/user_data.yml b/cluster/libvirt-coreos/user_data.yml
index 16d960dbfbe..ae7a430e972 100644
--- a/cluster/libvirt-coreos/user_data.yml
+++ b/cluster/libvirt-coreos/user_data.yml
@@ -16,9 +16,9 @@ write_files:
 coreos:
   etcd:
     name: ${name}
-    addr: 192.168.10.$(($i+1)):4001
+    addr: ${public_ip}:4001
     bind-addr: 0.0.0.0
-    peer-addr: 192.168.10.$(($i+1)):7001
+    peer-addr: ${public_ip}:7001
     # peers: {etcd_peers}
     discovery: ${discovery}
   units:
@@ -30,7 +30,7 @@ coreos:
         MACAddress=52:54:00:00:00:${i}
 
         [Network]
-        Address=192.168.10.$(($i+1))/24
+        Address=${public_ip}/24
         DNS=192.168.10.254
         Gateway=192.168.10.254
     - name: cbr0.netdev
@@ -46,10 +46,10 @@ coreos:
         Name=cbr0
 
         [Network]
-        Address=10.10.$(($i+1)).1/24
+        Address=${MINION_CONTAINER_SUBNETS[$i]}
 
         [Route]
-        Destination=10.10.0.0/16
+        Destination=${CONTAINER_SUBNET}
     - name: cbr0-interface.network
       command: start
       content: |
@@ -66,7 +66,7 @@ coreos:
         Description=NAT non container traffic
 
         [Service]
-        ExecStart=/usr/sbin/iptables -w -t nat -A POSTROUTING -o eth0 -j MASQUERADE ! -d 10.10.0.0/16
+        ExecStart=/usr/sbin/iptables -w -t nat -A POSTROUTING -o eth0 -j MASQUERADE ! -d ${CONTAINER_SUBNET}
         RemainAfterExit=yes
         Type=oneshot
     - name: etcd.service
diff --git a/cluster/libvirt-coreos/user_data_master.yml b/cluster/libvirt-coreos/user_data_master.yml
index 5f1b444198e..0efc5e7a5d4 100644
--- a/cluster/libvirt-coreos/user_data_master.yml
+++ b/cluster/libvirt-coreos/user_data_master.yml
@@ -18,7 +18,7 @@ coreos:
         --port=8080 \
         --etcd_servers=http://127.0.0.1:4001 \
         --kubelet_port=10250 \
-        --portal_net=10.10.254.0/24
+        --portal_net=${PORTAL_NET}
         Restart=always
         RestartSec=2
 
diff --git a/cluster/libvirt-coreos/user_data_minion.yml b/cluster/libvirt-coreos/user_data_minion.yml
index 139bba85134..d16abd09017 100644
--- a/cluster/libvirt-coreos/user_data_minion.yml
+++ b/cluster/libvirt-coreos/user_data_minion.yml
@@ -15,7 +15,7 @@ coreos:
         [Service]
         ExecStart=/opt/kubernetes/bin/kubelet \
         --address=0.0.0.0 \
-        --hostname_override=192.168.10.$(($i+1)) \
+        --hostname_override=${MINION_IPS[$i]} \
         --etcd_servers=http://127.0.0.1:4001
         Restart=always
         RestartSec=2
@@ -35,7 +35,7 @@ coreos:
         [Service]
         ExecStart=/opt/kubernetes/bin/kube-proxy \
         --etcd_servers=http://127.0.0.1:4001 \
-        --master=http://192.168.10.1:7080
+        --master=http://${MASTER_IP}:7080
         Restart=always
         RestartSec=2
 
diff --git a/cluster/libvirt-coreos/util.sh b/cluster/libvirt-coreos/util.sh
index 4c4a6f12a5f..d29737f9f27 100644
--- a/cluster/libvirt-coreos/util.sh
+++ b/cluster/libvirt-coreos/util.sh
@@ -38,8 +38,8 @@ function join {
 
 # Must ensure that the following ENV vars are set
 function detect-master {
-  KUBE_MASTER_IP=192.168.10.1
-  KUBE_MASTER=kubernetes-master
+  KUBE_MASTER_IP=$MASTER_IP
+  KUBE_MASTER=$MASTER_NAME
   export KUBERNETES_MASTER=http://$KUBE_MASTER_IP:8080
   echo "KUBE_MASTER_IP: $KUBE_MASTER_IP"
   echo "KUBE_MASTER: $KUBE_MASTER"
@@ -47,10 +47,7 @@ function detect-master {
 
 # Get minion IP addresses and store in KUBE_MINION_IP_ADDRESSES[]
 function detect-minions {
-  for (( i = 0 ; i < $NUM_MINIONS ; i++ )); do
-    KUBE_MINION_IP_ADDRESSES[$i]=192.168.10.$(($i+2))
-  done
-  echo "KUBE_MINION_IP_ADDRESSES=[${KUBE_MINION_IP_ADDRESSES[@]}]"
+  KUBE_MINION_IP_ADDRESSES=("${MINION_IPS[@]}")
 }
 
 # Verify prereqs on host machine
@@ -161,12 +158,15 @@ function kube-up {
 
   local i
   for (( i = 0 ; i <= $NUM_MINIONS ; i++ )); do
-    if [[ $i -eq 0 ]]; then
+    if [[ $i -eq $NUM_MINIONS ]]; then
         type=master
+        name=$MASTER_NAME
+        public_ip=$MASTER_IP
     else
       type=minion-$(printf "%02d" $i)
+      name=${MINION_NAMES[$i]}
+      public_ip=${MINION_IPS[$i]}
     fi
-    name=kubernetes_$type
     image=$name.img
     config=kubernetes_config_$type