diff --git a/labs/lib/functions.guest b/labs/lib/functions.guest
index c3bd25a3..cf6b7bd8 100644
--- a/labs/lib/functions.guest
+++ b/labs/lib/functions.guest
@@ -5,6 +5,13 @@
 source "$LIB_DIR/functions"
 source "$LIB_DIR/functions-common-devstack"
 
+# Make devstack's operating system identification work with nounset
+function init_os_ident {
+    if [[ -z "${os_PACKAGE:-""}" ]]; then
+        GetOSVersion
+    fi
+}
+
 function source_deploy {
     if [ -n "${VM_SHELL_USER:-}" ]; then
         # Already sourced
@@ -281,6 +288,7 @@ function _config_interfaces_hostonly {
 function config_nat {
     local if_num=$1
 
+    init_os_ident
     if is_fedora; then
         echo _config_sysconfig_nat "$if_num"
         _config_sysconfig_nat "$if_num"
@@ -294,6 +302,7 @@ function config_hostonly {
     local if_num=$1
     local ip_address=$2
 
+    init_os_ident
     if is_fedora; then
         echo _config_sysconfig_hostonly "$if_num" "$ip_address"
         _config_sysconfig_hostonly "$if_num" "$ip_address"
@@ -317,6 +326,7 @@ function hostname_to_ip {
 }
 
 function config_network {
+    init_os_ident
     if is_ubuntu; then
         # Configuration functions will append to this file
         sudo cp -v  "$TEMPLATE_DIR/template-ubuntu-interfaces-loopback" \
diff --git a/labs/scripts/apt_init.sh b/labs/scripts/apt_init.sh
index 0b416eb0..b9e2570c 100755
--- a/labs/scripts/apt_init.sh
+++ b/labs/scripts/apt_init.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/openstack"
diff --git a/labs/scripts/apt_install_mysql.sh b/labs/scripts/apt_install_mysql.sh
index 7853a952..2b8ecea4 100755
--- a/labs/scripts/apt_install_mysql.sh
+++ b/labs/scripts/apt_install_mysql.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/credentials"
diff --git a/labs/scripts/apt_pre-download.sh b/labs/scripts/apt_pre-download.sh
index 1b5b1a33..66be02bf 100755
--- a/labs/scripts/apt_pre-download.sh
+++ b/labs/scripts/apt_pre-download.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/openstack"
diff --git a/labs/scripts/apt_upgrade.sh b/labs/scripts/apt_upgrade.sh
index eb1c3a9c..917d3fe8 100755
--- a/labs/scripts/apt_upgrade.sh
+++ b/labs/scripts/apt_upgrade.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/openstack"
@@ -16,6 +17,7 @@ sudo apt-get -y dist-upgrade
 
 # XXX Not a great location for Vagrant specific code
 if [[ $VM_SHELL_USER = vagrant ]]; then
+    init_os_ident
     if is_ubuntu; then
         sudo apt-get -y install virtualbox-guest-dkms
     fi
diff --git a/labs/scripts/config_demo_user.sh b/labs/scripts/config_demo_user.sh
index 3633467c..ce1683a8 100755
--- a/labs/scripts/config_demo_user.sh
+++ b/labs/scripts/config_demo_user.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/credentials"
diff --git a/labs/scripts/config_external_network.sh b/labs/scripts/config_external_network.sh
index 5ecab7a0..cfe87165 100755
--- a/labs/scripts/config_external_network.sh
+++ b/labs/scripts/config_external_network.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/credentials"
diff --git a/labs/scripts/config_tenant_network.sh b/labs/scripts/config_tenant_network.sh
index c638d4ca..e1c23735 100755
--- a/labs/scripts/config_tenant_network.sh
+++ b/labs/scripts/config_tenant_network.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/credentials"
diff --git a/labs/scripts/etc_hosts.sh b/labs/scripts/etc_hosts.sh
index 13402f0c..fa1fdc39 100755
--- a/labs/scripts/etc_hosts.sh
+++ b/labs/scripts/etc_hosts.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$LIB_DIR/functions.guest"
diff --git a/labs/scripts/install_rabbitmq.sh b/labs/scripts/install_rabbitmq.sh
index 2ccb41a7..c38f567f 100755
--- a/labs/scripts/install_rabbitmq.sh
+++ b/labs/scripts/install_rabbitmq.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/credentials"
diff --git a/labs/scripts/osbash/activate_autostart.sh b/labs/scripts/osbash/activate_autostart.sh
index df333abc..f5bb8ebf 100755
--- a/labs/scripts/osbash/activate_autostart.sh
+++ b/labs/scripts/osbash/activate_autostart.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 # This script is the first to run and the only one to run as root.
 
 # XXX The name activate_autostart.sh is hard-coded in ks.cfg and preseed.cfg.
@@ -52,6 +53,9 @@ sed -e "
 
 chmod 755 "/etc/init.d/$RCAUTOSTART"
 
+# Make devstack's is_fedora work with nounset
+init_os_ident
+
 if is_fedora; then
     cat << SERVICE > /etc/systemd/system/$RCAUTOSTART.service
 [Unit]
diff --git a/labs/scripts/osbash/base_fixups.sh b/labs/scripts/osbash/base_fixups.sh
index f6b89a66..84ff7437 100755
--- a/labs/scripts/osbash/base_fixups.sh
+++ b/labs/scripts/osbash/base_fixups.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$LIB_DIR/functions.guest"
diff --git a/labs/scripts/osbash/enable_vagrant_ssh_keys.sh b/labs/scripts/osbash/enable_vagrant_ssh_keys.sh
index e17cdbc3..7be3a77c 100755
--- a/labs/scripts/osbash/enable_vagrant_ssh_keys.sh
+++ b/labs/scripts/osbash/enable_vagrant_ssh_keys.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 
 # This script installs the unsecure Vagrant ssh keys. This allows users to
 # log into the VMs using these keys instead of a password.
diff --git a/labs/scripts/osbash/init_xxx_node.sh b/labs/scripts/osbash/init_xxx_node.sh
index b77c3207..684cf2a5 100755
--- a/labs/scripts/osbash/init_xxx_node.sh
+++ b/labs/scripts/osbash/init_xxx_node.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 
 # This scripts configures hostname and networking for all nodes. The filename
 # determines the node name.
diff --git a/labs/scripts/osbash/wait_debug.sh b/labs/scripts/osbash/wait_debug.sh
index 2bb41fe3..d426b688 100755
--- a/labs/scripts/osbash/wait_debug.sh
+++ b/labs/scripts/osbash/wait_debug.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$LIB_DIR/functions.guest"
diff --git a/labs/scripts/setup_cinder_controller.sh b/labs/scripts/setup_cinder_controller.sh
index ce10bce3..44e76000 100755
--- a/labs/scripts/setup_cinder_controller.sh
+++ b/labs/scripts/setup_cinder_controller.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/credentials"
diff --git a/labs/scripts/setup_cinder_volumes.sh b/labs/scripts/setup_cinder_volumes.sh
index ff6d0a85..7c1c20c0 100755
--- a/labs/scripts/setup_cinder_volumes.sh
+++ b/labs/scripts/setup_cinder_volumes.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/credentials"
diff --git a/labs/scripts/setup_glance.sh b/labs/scripts/setup_glance.sh
index af67bdc8..d5210e63 100755
--- a/labs/scripts/setup_glance.sh
+++ b/labs/scripts/setup_glance.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/credentials"
diff --git a/labs/scripts/setup_horizon.sh b/labs/scripts/setup_horizon.sh
index 2f093022..80b55d51 100755
--- a/labs/scripts/setup_horizon.sh
+++ b/labs/scripts/setup_horizon.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$LIB_DIR/functions.guest"
diff --git a/labs/scripts/setup_keystone.sh b/labs/scripts/setup_keystone.sh
index e179183f..b756063a 100755
--- a/labs/scripts/setup_keystone.sh
+++ b/labs/scripts/setup_keystone.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/credentials"
diff --git a/labs/scripts/setup_neutron_compute.sh b/labs/scripts/setup_neutron_compute.sh
index 7013c037..6d6ab1d2 100755
--- a/labs/scripts/setup_neutron_compute.sh
+++ b/labs/scripts/setup_neutron_compute.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/credentials"
diff --git a/labs/scripts/setup_neutron_controller.sh b/labs/scripts/setup_neutron_controller.sh
index 9c0464bc..9fc70b2f 100755
--- a/labs/scripts/setup_neutron_controller.sh
+++ b/labs/scripts/setup_neutron_controller.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/credentials"
diff --git a/labs/scripts/setup_neutron_network.sh b/labs/scripts/setup_neutron_network.sh
index 0a5ec3d6..4c1fa869 100755
--- a/labs/scripts/setup_neutron_network.sh
+++ b/labs/scripts/setup_neutron_network.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/credentials"
@@ -91,7 +92,9 @@ log-queries
 # Verbose logging for DHCP
 log-dhcp
 DNSMASQ
-sudo killall dnsmasq
+
+# Catch and ignore error status if no dnsmasq process is found (the default)
+sudo killall dnsmasq||rc=$?
 
 echo "Configuring the metadata agent"
 conf=/etc/neutron/metadata_agent.ini
diff --git a/labs/scripts/setup_nova_compute.sh b/labs/scripts/setup_nova_compute.sh
index 2a2493ec..38de73c0 100755
--- a/labs/scripts/setup_nova_compute.sh
+++ b/labs/scripts/setup_nova_compute.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/credentials"
diff --git a/labs/scripts/setup_nova_controller.sh b/labs/scripts/setup_nova_controller.sh
index 35bb0217..434a49d9 100755
--- a/labs/scripts/setup_nova_controller.sh
+++ b/labs/scripts/setup_nova_controller.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/credentials"
diff --git a/labs/scripts/shutdown.sh b/labs/scripts/shutdown.sh
index fd51ab82..ea959a2e 100755
--- a/labs/scripts/shutdown.sh
+++ b/labs/scripts/shutdown.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$LIB_DIR/functions.guest"
diff --git a/labs/scripts/yum_init.sh b/labs/scripts/yum_init.sh
index 95c761cb..3fc78d39 100755
--- a/labs/scripts/yum_init.sh
+++ b/labs/scripts/yum_init.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/openstack"
diff --git a/labs/scripts/yum_update.sh b/labs/scripts/yum_update.sh
index 6cb13e34..5825459d 100755
--- a/labs/scripts/yum_update.sh
+++ b/labs/scripts/yum_update.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$CONFIG_DIR/openstack"
diff --git a/labs/scripts/zero_empty.sh b/labs/scripts/zero_empty.sh
index bfff5fd5..dceab9e1 100755
--- a/labs/scripts/zero_empty.sh
+++ b/labs/scripts/zero_empty.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -o errexit -o nounset
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 source "$TOP_DIR/config/paths"
 source "$LIB_DIR/functions.guest"