diff --git a/de/heat-templates/scripts/instance_boot.sh b/de/heat-templates/scripts/instance_boot.sh
index 2d5db67..db1a290 100644
--- a/de/heat-templates/scripts/instance_boot.sh
+++ b/de/heat-templates/scripts/instance_boot.sh
@@ -718,18 +718,21 @@
 function collect_interfaces_metadata {
 
     local if_metadata_file="/usr/share/metadata/interfaces.yaml"
+    if [ -z "${TUNNEL_INTERFACE}" ] ; then
+        echo "Tunnel interface is empty"
+    else
+        pci_id=$(ethtool -i ${TUNNEL_INTERFACE} |grep bus-info | awk '{print $2}')
+        mac=$(cat $(find /sys/bus/pci/devices/${pci_id}/ -name net)/${TUNNEL_INTERFACE}/address)
+        ip=${TUNNEL_INTERFACE_IP}/${TUNNEL_INTERFACE_NETWORK_NETMASK}
 
-    pci_id=$(ethtool -i ${TUNNEL_INTERFACE} |grep bus-info | awk '{print $2}')
-    mac=$(cat $(find /sys/bus/pci/devices/${pci_id}/ -name net)/${TUNNEL_INTERFACE}/address)
-    ip=${TUNNEL_INTERFACE_IP}/${TUNNEL_INTERFACE_NETWORK_NETMASK}
-
-    cat << EOF > ${if_metadata_file}
+        cat << EOF > ${if_metadata_file}
 ${TUNNEL_INTERFACE}:
   pci_id: "${pci_id}"
   ip_addr: "${ip}"
   mac: "${mac}"
 EOF
 
+    fi
     HW_METADATA=$(echo ${HW_METADATA} | jq -cr ". += {\"interfaces\": {\"$(hostname)\": \"$(base64 -w 0 ${if_metadata_file})\"}}")
 
 }