diff --git a/devstack/tools/ironic/scripts/configure-vm.py b/devstack/tools/ironic/scripts/configure-vm.py
index dee17b886f..18590279ae 100755
--- a/devstack/tools/ironic/scripts/configure-vm.py
+++ b/devstack/tools/ironic/scripts/configure-vm.py
@@ -91,6 +91,8 @@ def main():
                         help=('The absolute path of the non-volatile memory '
                               'to store the UEFI variables. Should be used '
                               'only when --uefi-loader is also specified.'))
+    parser.add_argument('--block-size', default='512',
+                        help='The block size for the block storage.')
     args = parser.parse_args()
 
     env = jinja2.Environment(loader=jinja2.FileSystemLoader(templatedir))
@@ -117,6 +119,7 @@ def main():
         'disk_format': args.disk_format,
         'uefi_loader': args.uefi_loader,
         'uefi_nvram': args.uefi_nvram,
+        'block_size': args.block_size,
     }
 
     if args.emulator:
diff --git a/devstack/tools/ironic/scripts/create-node.sh b/devstack/tools/ironic/scripts/create-node.sh
index 8530b846ff..5cca0ffc25 100755
--- a/devstack/tools/ironic/scripts/create-node.sh
+++ b/devstack/tools/ironic/scripts/create-node.sh
@@ -12,7 +12,7 @@ export PS4='+ ${BASH_SOURCE:-}:${FUNCNAME[0]:-}:L${LINENO:-}:   '
 # Keep track of the DevStack directory
 TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
 
-while getopts "n:c:i:m:M:d:a:b:e:E:p:o:f:l:L:N:A:D:v:P:t:" arg; do
+while getopts "n:c:i:m:M:d:a:b:e:E:p:o:f:l:L:N:A:D:v:P:t:B:" arg; do
     case $arg in
         n) NAME=$OPTARG;;
         c) CPU=$OPTARG;;
@@ -37,6 +37,7 @@ while getopts "n:c:i:m:M:d:a:b:e:E:p:o:f:l:L:N:A:D:v:P:t:" arg; do
         v) VOLUME_COUNT=$OPTARG;;
         P) STORAGE_POOL=$OPTARG;;
         t) MACHINE_TYPE=$OPTARG;;
+        B) BLOCK_SIZE=$OPTARG;;
     esac
 done
 
@@ -77,6 +78,8 @@ if [ ! -z "$UEFI_LOADER" ]; then
     fi
 fi
 
+BLOCK_SIZE=${BLOCK_SIZE:-512}
+
 # Create bridge and add VM interface to it.
 # Additional interface will be added to this bridge and
 # it will be plugged to OVS.
@@ -129,7 +132,8 @@ if ! virsh list --all | grep -q $NAME; then
         --bootdev network --name $NAME \
         --arch $ARCH --cpus $CPU --memory $MEM --libvirt-nic-driver $LIBVIRT_NIC_DRIVER \
         --disk-format $DISK_FORMAT $VM_LOGGING --engine $ENGINE $UEFI_OPTS $vm_opts \
-        --interface-count $INTERFACE_COUNT $MAC_ADDRESS --machine_type $MACHINE_TYPE >&2
+        --interface-count $INTERFACE_COUNT $MAC_ADDRESS --machine_type $MACHINE_TYPE \
+        --block-size $BLOCK_SIZE >&2
 fi
 
 # echo mac in format mac1,ovs-node-0i1;mac2,ovs-node-0i2;...;macN,ovs-node0iN
diff --git a/devstack/tools/ironic/templates/vm.xml b/devstack/tools/ironic/templates/vm.xml
index bd36e9f360..f91b166b78 100644
--- a/devstack/tools/ironic/templates/vm.xml
+++ b/devstack/tools/ironic/templates/vm.xml
@@ -46,6 +46,7 @@
       <driver name='qemu' type='{{ disk_format }}' cache='unsafe'/>
       <source file='{{ imagefile }}'/>
       <target dev='vd{{ letter }}'/>
+      <blockio logical_block_size="{{ block_size }}" physical_block_size="{{ block_size }}" discard_granularity="{{ block_size }}"/>
     </disk>
     {% endfor %}
     {% for n in range(1, interface_count+1) %}