diff --git a/k8s/workspace/update-openstack-resources.sh b/k8s/workspace/update-openstack-resources.sh
index 75d1216..e292bda 100644
--- a/k8s/workspace/update-openstack-resources.sh
+++ b/k8s/workspace/update-openstack-resources.sh
@@ -50,6 +50,17 @@
 sed -i "s/volume_type_name/${TEMPEST_CUSTOM_VOLUME_TYPE}/g" $MY_PROJFOLDER/yamls/tempest_custom.yaml
 echo " "
 
+echo "# Checking Neutron global physnet mtu value"
+global_physnet_mtu=""
+global_physnet_mtu=$(kubectl get osdpl -A -o wide -o yaml | grep global_physnet_mtu | tail -n1 | cut -d':' -f2 | tr -d ' ')
+if [ -n "$global_physnet_mtu" ]; then
+    echo "global_physnet_mtu is set to: $global_physnet_mtu"
+    cat <<EOF >> $MY_PROJFOLDER/yamls/tempest_custom.yaml
+neutron_plugin_options:
+    max_mtu: $global_physnet_mtu
+EOF
+fi
+
 echo "# Updating SPT global_config.yaml"
 cp -v /opt/res-files/k8s/yamls/spt_global_config.yaml.clean $MY_PROJFOLDER/yamls/global_config.yaml
 echo "# image_ref_name -> ${ubuntu20_name}"
diff --git a/k8s/yamls/tempest_custom.yaml.clean b/k8s/yamls/tempest_custom.yaml.clean
index 5db71af..6a65e4f 100644
--- a/k8s/yamls/tempest_custom.yaml.clean
+++ b/k8s/yamls/tempest_custom.yaml.clean
@@ -7,7 +7,6 @@
     disable_ssl_certificate_validation: true
 compute:
     volume_device_name: vdb
-    compute_volume_common_az: nova
 heat_plugin:
     floating_network_name: public_net_name
     network_for_ssh: public_net_name
@@ -18,5 +17,4 @@
 network-feature-enabled:
     floating_ips: true
 volume:
-    volume_type: volume_type_name
-    volume_type_multiattach: volume_type_name
\ No newline at end of file
+    volume_type: volume_type_name
\ No newline at end of file
diff --git a/scripts/prepare.sh b/scripts/prepare.sh
index 0a04eec..fbf2abc 100644
--- a/scripts/prepare.sh
+++ b/scripts/prepare.sh
@@ -10,6 +10,7 @@
 rcfile=${name_prefix}rc
 huge_pages=false
 set_gw_heat_router=false
+raw_disk_format=false
 logfile=prepare.log
 working_folder=$(pwd)
 
@@ -66,10 +67,11 @@
     printf "\t-H\t\tAdds '--property hw:mem_page_size=large' to flavors, i.e. huge_pages for DPDK\n"
     printf "\t-w <path>\tSets working folder (default: ${working_folder})\n"
     printf "\t-g\t\tTo set external_gateway_info to heat-router with the external network (if not set yet)\n"
+    printf "\t-r\t\tTo create the images in RAW disk format instead of the QCOW2\n"
 }
 
 OPTIND=1 # Reset in case getopts has been used previously in the shell.
-while getopts ":gHw:h?"  opt; do
+while getopts ":grHw:h?"  opt; do
     case "$opt" in
     h|\?)
         show_help
@@ -84,6 +86,9 @@
     g)  set_gw_heat_router=true
         printf "# Setting external_gateway_info to heat-router with the external network (if not set yet)\n\n"
         ;;
+    r)  raw_disk_format=true
+        printf "# Creating the images in RAW disk format instead of the QCOW2\n"
+        ;;
     esac
 done
 
@@ -384,8 +389,15 @@
         fi
         # check if output is not empty
         if [ ${#r} -eq 0 ]; then
+          if [ "$raw_disk_format" = true ]; then
+            qemu-img convert -f qcow2 -O raw ${!name} ${!name}.raw
+            image_id=$(openstack image create --public --disk-format raw --container-format bare --file ${!name}.raw ${!name} -c id -f value)
+            echo "-> created ${!name} (${image_id})"
+            rm ${!name}.raw
+          else
             image_id=$(openstack image create --public --disk-format qcow2 --container-format bare --file ${!name} ${!name} -c id -f value)
             echo "-> created ${!name} (${image_id})"
+          fi
         else
             printf "\n-> Error detected, creation skipped\n"
         fi