diff --git a/icebox/cluster/rackspace/cloud-config/master-cloud-config.yaml b/icebox/cluster/rackspace/cloud-config/master-cloud-config.yaml
index cec8bf2e13a..a9b3800eea9 100644
--- a/icebox/cluster/rackspace/cloud-config/master-cloud-config.yaml
+++ b/icebox/cluster/rackspace/cloud-config/master-cloud-config.yaml
@@ -7,6 +7,7 @@ write_files:
         - kubernetes-master
       cloud: rackspace
       etcd_servers: KUBE_MASTER
+      portal_net: PORTAL_NET
   path: /etc/salt/minion.d/grains.conf
 - content: |
     auto_accept: True
diff --git a/icebox/cluster/rackspace/config-default.sh b/icebox/cluster/rackspace/config-default.sh
index 4febe577102..6d4837a6fc7 100644
--- a/icebox/cluster/rackspace/config-default.sh
+++ b/icebox/cluster/rackspace/config-default.sh
@@ -36,3 +36,4 @@ RAX_NUM_MINIONS="${RAX_NUM_MINIONS-4}"
 MINION_TAG="tag=${INSTANCE_PREFIX}-minion"
 MINION_NAMES=($(eval echo ${INSTANCE_PREFIX}-minion-{1..${RAX_NUM_MINIONS}}))
 KUBE_NETWORK=($(eval echo "10.240.{1..${RAX_NUM_MINIONS}}.0/24"))
+PORTAL_NET="10.0.0.0/16"
diff --git a/icebox/cluster/rackspace/util.sh b/icebox/cluster/rackspace/util.sh
index fc667e13632..30a3293894f 100644
--- a/icebox/cluster/rackspace/util.sh
+++ b/icebox/cluster/rackspace/util.sh
@@ -70,9 +70,11 @@ rax-boot-master() {
   grep -v "^#" $(dirname $0)/templates/download-release.sh
   ) > ${KUBE_TEMP}/masterStart.sh
 
-# Copy cloud-config to KUBE_TEMP and work some sed magic
-  sed -e "s/KUBE_MASTER/$MASTER_NAME/g" \
-      -e "s/MASTER_HTPASSWD/$HTPASSWD/" \
+# Copy cloud-config to KUBE_TEMP and work some sed magic.  Some vars can have
+# '/' embedded, so don't use that for sed.
+  sed -e "s|KUBE_MASTER|$MASTER_NAME|g" \
+      -e "s|MASTER_HTPASSWD|$HTPASSWD|" \
+      -e "s|PORTAL_NET|$PORTAL_NET|" \
       $(dirname $0)/cloud-config/master-cloud-config.yaml > $KUBE_TEMP/master-cloud-config.yaml