diff --git a/lib/fog/libvirt/models/compute/server.rb b/lib/fog/libvirt/models/compute/server.rb
index 56ef222..f0ffb0e 100644
--- a/lib/fog/libvirt/models/compute/server.rb
+++ b/lib/fog/libvirt/models/compute/server.rb
@@ -368,7 +368,9 @@ def to_xml
                   else
                     is_block = volume.path.start_with?("/dev/")
                     xml.disk(:type => is_block ? "block" : "file", :device => "disk") do
-                      xml.driver(:name => "qemu", :type => volume.format_type)
+                      driver = xml.driver(:name => "qemu")
+                      driver[:type] = volume.format_type if volume.format_type
+
                       if is_block
                         xml.source(:dev => volume.path)
                       else
diff --git a/lib/fog/libvirt/models/compute/volume.rb b/lib/fog/libvirt/models/compute/volume.rb
index 12b60ef..3699da1 100644
--- a/lib/fog/libvirt/models/compute/volume.rb
+++ b/lib/fog/libvirt/models/compute/volume.rb
@@ -91,7 +91,7 @@ def to_xml
               xml.capacity(capacity_size, :unit => capacity_unit)
 
               xml.target do
-                xml.format(:type => format_type)
+                xml.format(:type => format_type) if format_type
                 xml_permissions(xml)
               end
 
diff --git a/tests/libvirt/models/compute/server_tests.rb b/tests/libvirt/models/compute/server_tests.rb
index 448baef..10db92c 100644
--- a/tests/libvirt/models/compute/server_tests.rb
+++ b/tests/libvirt/models/compute/server_tests.rb
@@ -129,5 +129,39 @@
 
       os_firmware && secure_boot && enrolled_keys && loader_attributes
     end
+
+    test("with volumes") do
+      pool = Fog::Compute[:libvirt].pools.create(
+        :persistent => true,
+        :xml => <<~XML
+          <pool type='logical'>
+            <name>lvm-pool</name>
+            <source>
+              <name>vg_storage01</name>
+              <format type='lvm2'/>
+            </source>
+            <target>
+              <path>/dev/vg_storage01</path>
+            </target>
+          </pool>
+        XML
+      )
+      server = Fog::Compute[:libvirt].servers.new(
+        :nics => [],
+        :volumes => [
+          {
+            :path => "/dev/vg_storage01/volume01",
+            :pool_name => pool.name
+          }
+        ]
+      )
+      server.volumes.each do |volume|
+        volume.save
+        # mock driver doesn't simulate the real thing
+        # LVM doesn't have a volume type
+        volume.format_type = nil
+      end
+      !server.save.nil?
+    end
   end
 end