diff --git a/lib/vagrant-libvirt/action/start_domain.rb b/lib/vagrant-libvirt/action/start_domain.rb
index b7458a7..dc89934 100644
--- a/lib/vagrant-libvirt/action/start_domain.rb
+++ b/lib/vagrant-libvirt/action/start_domain.rb
@@ -1,5 +1,6 @@
 # frozen_string_literal: true
 
+require 'diffy'
 require 'log4r'
 require 'rexml/document'
 
@@ -14,8 +15,6 @@ module VagrantPlugins
         end
 
         def call(env)
-          env[:ui].info(I18n.t('vagrant_libvirt.starting_domain'))
-
           domain = env[:machine].provider.driver.connection.servers.get(env[:machine].id.to_s)
           raise Errors::NoDomainError if domain.nil?
           config = env[:machine].provider_config
@@ -33,6 +32,7 @@ module VagrantPlugins
                 libvirt_domain.memory = libvirt_domain.max_memory
               end
             end
+
             begin
               # XML definition manipulation
               descr = libvirt_domain.xml_desc(1)
@@ -248,7 +248,7 @@ module VagrantPlugins
               # TPM
               if [config.tpm_path, config.tpm_version].any?
                 if config.tpm_path
-                  raise Errors::FogCreateServerError, 'The TPM Path must be fully qualified' unless config.tpm_path[0].chr == '/'
+                  raise Errors::UpdateServerError, 'The TPM Path must be fully qualified' unless config.tpm_path[0].chr == '/'
                 end
 
                 # just build the tpm element every time
@@ -394,7 +394,6 @@ module VagrantPlugins
                 loader.parent.delete_element(loader)
               end
 
-              undefine_flags = 0
               nvram = REXML::XPath.first(xml_descr, '/domain/os/nvram')
               if config.nvram
                 if nvram.nil?
@@ -407,28 +406,57 @@ module VagrantPlugins
                     descr_changed = true
                     nvram.text = config.nvram
                   end
-                  undefine_flags |= ProviderLibvirt::Util::DomainFlags::VIR_DOMAIN_UNDEFINE_KEEP_NVRAM
                 end
               elsif !nvram.nil?
                 descr_changed = true
-                undefine_flags |= ProviderLibvirt::Util::DomainFlags::VIR_DOMAIN_UNDEFINE_NVRAM
                 nvram.parent.delete_element(nvram)
               end
 
               # Apply
               if descr_changed
+                env[:ui].info(I18n.t('vagrant_libvirt.updating_domain'))
+                new_xml = String.new
+                xml_descr.write(new_xml)
                 begin
-                  libvirt_domain.undefine(undefine_flags)
-                  new_descr = String.new
-                  xml_descr.write new_descr
-                  env[:machine].provider.driver.connection.servers.create(xml: new_descr)
-                rescue Fog::Errors::Error => e
-                  env[:machine].provider.driver.connection.servers.create(xml: descr)
-                  raise Errors::FogCreateServerError, error_message: e.message
+                  # providing XML for the same name and UUID will update the existing domain
+                  libvirt_domain = env[:machine].provider.driver.connection.define_domain(new_xml)
+                rescue ::Libvirt::Error => e
+                  raise Errors::UpdateServerError, error_message: e.message
+                end
+
+                begin
+                  proposed = Nokogiri::XML(new_xml, &:noblanks)
+
+                  # This normalizes the attribute order to be consistent across both XML docs to eliminate differences
+                  # for subsequent comparison by diffy
+                  updated_xml_descr = REXML::Document.new(libvirt_domain.xml_desc(1))
+                  updated_xml = String.new
+                  updated_xml_descr.write(updated_xml)
+
+                  updated = Nokogiri::XML(updated_xml, &:noblanks)
+
+                  pretty_proposed = StringIO.new
+                  pretty_updated = StringIO.new
+                  proposed.write_xml_to(pretty_proposed, indent: 2)
+                  updated.write_xml_to(pretty_updated, indent: 2)
+
+                  diff = Diffy::Diff.new(pretty_proposed.string, pretty_updated.string, :context => 3).to_s(:text)
+
+                  unless diff.empty?
+                    error_msg = "Libvirt failed to fully update the domain with the specified XML. Result differs from requested:\n" +
+                      "--- requested\n+++ result\n#{diff}\n" +
+                      "Typically this means there is a bug in the XML being sent, please log an issue"
+
+                    raise Errors::UpdateServerError, error_message: error_msg
+                  end
+                rescue Exception => e
+                  env[:machine].provider.driver.connection.define_domain(descr)
+                  raise
                 end
               end
             rescue Errors::VagrantLibvirtError => e
               env[:ui].error("Error when updating domain settings: #{e.message}")
+              raise
             end
             # Autostart with host if enabled in Vagrantfile
             libvirt_domain.autostart = config.autostart
@@ -436,6 +464,7 @@ module VagrantPlugins
               "Starting Domain with XML:\n#{libvirt_domain.xml_desc}"
             }
             # Actually start the domain
+            env[:ui].info(I18n.t('vagrant_libvirt.starting_domain'))
             domain.start
           rescue Fog::Errors::Error, Errors::VagrantLibvirtError => e
             raise Errors::FogError, message: e.message
diff --git a/lib/vagrant-libvirt/errors.rb b/lib/vagrant-libvirt/errors.rb
index f006193..caf2203 100644
--- a/lib/vagrant-libvirt/errors.rb
+++ b/lib/vagrant-libvirt/errors.rb
@@ -109,7 +109,7 @@ module VagrantPlugins
       end
 
       class FogCreateServerError < VagrantLibvirtError
-        error_key(:fog_create_server_error)
+        error_key(:create_server_error)
       end
 
       # Network exceptions
@@ -154,6 +154,10 @@ module VagrantPlugins
       end
 
       # Other exceptions
+      class UpdateServerError < VagrantLibvirtError
+        error_key(:create_server_error)
+      end
+
       class InterfaceSlotNotAvailable < VagrantLibvirtError
         error_key(:interface_slot_not_available)
       end
diff --git a/locales/en.yml b/locales/en.yml
index af8d2a4..75346d5 100644
--- a/locales/en.yml
+++ b/locales/en.yml
@@ -25,6 +25,8 @@ en:
       Creating image (snapshot of base box volume).
     removing_domain_volume: |-
       Removing image (snapshot of base box volume).
+    updating_domain: |-
+      Updating domain definition due to configuration change
     starting_domain: |-
       Starting domain.
     terminating: |-
@@ -138,7 +140,7 @@ en:
         Error while creating a storage pool volume: %{error_message}
       fog_create_domain_volume_error: |-
         Error while creating volume for domain: %{error_message}
-      fog_create_server_error: |-
+      create_server_error: |-
         Error while creating domain: %{error_message}
       domain_name_exists: |-
         Name `%{domain_name}` of domain about to create is already taken. Please try to run
diff --git a/spec/unit/action/start_domain_spec.rb b/spec/unit/action/start_domain_spec.rb
index 221e5b2..ac30a83 100644
--- a/spec/unit/action/start_domain_spec.rb
+++ b/spec/unit/action/start_domain_spec.rb
@@ -33,8 +33,7 @@ describe VagrantPlugins::ProviderLibvirt::Action::StartDomain do
       allow(servers).to receive(:get).and_return(domain)
 
       allow(logger).to receive(:debug)
-      expect(logger).to receive(:info)
-      expect(ui).to_not receive(:error)
+      allow(logger).to receive(:info)
 
       allow(libvirt_domain).to receive(:xml_desc).and_return(domain_xml)
 
@@ -43,23 +42,53 @@ describe VagrantPlugins::ProviderLibvirt::Action::StartDomain do
     end
 
     it 'should execute without changing' do
-      expect(libvirt_domain).to_not receive(:undefine)
+      expect(ui).to_not receive(:error)
+      expect(libvirt_client).to_not receive(:define_domain_xml)
       expect(libvirt_domain).to receive(:autostart=)
       expect(domain).to receive(:start)
 
       expect(subject.call(env)).to be_nil
     end
 
-    context 'when previously running default config' do
-      let(:test_file) { 'existing.xml' }
+    context 'when any setting changed' do
+      let(:vagrantfile_providerconfig) do
+        <<-EOF
+        libvirt.cpus = 2
+        EOF
+      end
 
-      it 'should execute without changing' do
-        expect(libvirt_domain).to_not receive(:undefine)
+      let(:updated_domain_xml) {
+        new_xml = domain_xml.dup
+        new_xml['<vcpu>1</vcpu>'] = '<vcpu>2</vcpu>'
+        new_xml
+      }
+
+      it 'should update the domain' do
+        expect(ui).to_not receive(:error)
         expect(libvirt_domain).to receive(:autostart=)
+        expect(connection).to receive(:define_domain).and_return(libvirt_domain)
+        expect(libvirt_domain).to receive(:xml_desc).and_return(domain_xml, updated_domain_xml)
         expect(domain).to receive(:start)
 
         expect(subject.call(env)).to be_nil
       end
+
+      context 'when there is an error during update' do
+        it 'should skip attempting to start' do
+          expect(ui).to receive(:error)
+          expect(connection).to receive(:define_domain).and_raise(::Libvirt::Error)
+
+          expect { subject.call(env) }.to raise_error(VagrantPlugins::ProviderLibvirt::Errors::VagrantLibvirtError)
+        end
+      end
+
+      context 'when there is an interrupt' do
+        it 'should skip attempting to start' do
+          expect(connection).to receive(:define_domain).and_raise(Interrupt)
+
+          expect { subject.call(env) }.to raise_error(Interrupt)
+        end
+      end
     end
 
     context 'nvram' do
@@ -73,9 +102,10 @@ describe VagrantPlugins::ProviderLibvirt::Action::StartDomain do
         let(:test_file) { 'existing.xml' }
         let(:updated_test_file) { 'existing_added_nvram.xml' }
 
-        it 'should undefine without passing flags' do
-          expect(libvirt_domain).to receive(:undefine).with(0)
-          expect(servers).to receive(:create).with(xml: updated_domain_xml)
+        it 'should add the nvram element' do
+          expect(ui).to_not receive(:error)
+          expect(connection).to receive(:define_domain).with(updated_domain_xml).and_return(libvirt_domain)
+          expect(libvirt_domain).to receive(:xml_desc).and_return(domain_xml, updated_domain_xml)
           expect(libvirt_domain).to receive(:autostart=)
           expect(domain).to receive(:start)
 
@@ -87,17 +117,16 @@ describe VagrantPlugins::ProviderLibvirt::Action::StartDomain do
         let(:vagrantfile_providerconfig) do
           <<-EOF
           libvirt.loader = "/path/to/loader/file"
-          libvirt.nvram = "/path/to/nvram/file"
-          # change another setting to trigger the undefine/create
-          libvirt.cpus = 4
+          libvirt.nvram = "/path/to/nvram/file1"
           EOF
         end
         let(:test_file) { 'nvram_domain.xml' }
         let(:updated_test_file) { 'nvram_domain_other_setting.xml' }
 
-        it 'should set the flag to keep nvram' do
-          expect(libvirt_domain).to receive(:undefine).with(VagrantPlugins::ProviderLibvirt::Util::DomainFlags::VIR_DOMAIN_UNDEFINE_KEEP_NVRAM)
-          expect(servers).to receive(:create).with(xml: updated_domain_xml)
+        it 'should keep the XML element' do
+          expect(ui).to_not receive(:error)
+          expect(connection).to receive(:define_domain).with(updated_domain_xml).and_return(libvirt_domain)
+          expect(libvirt_domain).to receive(:xml_desc).and_return(domain_xml, updated_domain_xml)
           expect(libvirt_domain).to receive(:autostart=)
           expect(domain).to receive(:start)
 
@@ -108,9 +137,10 @@ describe VagrantPlugins::ProviderLibvirt::Action::StartDomain do
           let(:vagrantfile_providerconfig) { }
           let(:updated_test_file) { 'nvram_domain_removed.xml' }
 
-          it 'should set the flag to remove nvram' do
-            expect(libvirt_domain).to receive(:undefine).with(VagrantPlugins::ProviderLibvirt::Util::DomainFlags::VIR_DOMAIN_UNDEFINE_NVRAM)
-            expect(servers).to receive(:create).with(xml: updated_domain_xml)
+          it 'should delete the XML element' do
+            expect(ui).to_not receive(:error)
+            expect(connection).to receive(:define_domain).with(updated_domain_xml).and_return(libvirt_domain)
+            expect(libvirt_domain).to receive(:xml_desc).and_return(domain_xml, updated_domain_xml)
             expect(libvirt_domain).to receive(:autostart=)
             expect(domain).to receive(:start)
 
@@ -132,9 +162,10 @@ describe VagrantPlugins::ProviderLibvirt::Action::StartDomain do
         end
 
         it 'should modify the domain tpm_path' do
-          expect(libvirt_domain).to receive(:undefine)
+          expect(ui).to_not receive(:error)
           expect(logger).to receive(:debug).with('tpm config changed')
-          expect(servers).to receive(:create).with(xml: updated_domain_xml)
+          expect(connection).to receive(:define_domain).with(updated_domain_xml).and_return(libvirt_domain)
+          expect(libvirt_domain).to receive(:xml_desc).and_return(domain_xml, updated_domain_xml)
           expect(libvirt_domain).to receive(:autostart=)
           expect(domain).to receive(:start)
 
@@ -153,9 +184,10 @@ describe VagrantPlugins::ProviderLibvirt::Action::StartDomain do
         end
 
         it 'should modify the domain tpm_path' do
-          expect(libvirt_domain).to receive(:undefine)
+          expect(ui).to_not receive(:error)
           expect(logger).to receive(:debug).with('tpm config changed')
-          expect(servers).to receive(:create).with(xml: updated_domain_xml)
+          expect(connection).to receive(:define_domain).with(updated_domain_xml).and_return(libvirt_domain)
+          expect(libvirt_domain).to receive(:xml_desc).and_return(domain_xml, updated_domain_xml)
           expect(libvirt_domain).to receive(:autostart=)
           expect(domain).to receive(:start)
 
@@ -175,6 +207,7 @@ describe VagrantPlugins::ProviderLibvirt::Action::StartDomain do
         end
 
         it 'should execute without changing' do
+          expect(ui).to_not receive(:error)
           expect(libvirt_domain).to receive(:autostart=)
           expect(domain).to receive(:start)
 
@@ -194,6 +227,7 @@ describe VagrantPlugins::ProviderLibvirt::Action::StartDomain do
         end
 
         it 'should execute without changing' do
+          expect(ui).to_not receive(:error)
           expect(libvirt_domain).to receive(:autostart=)
           expect(domain).to receive(:start)
 
@@ -213,9 +247,10 @@ describe VagrantPlugins::ProviderLibvirt::Action::StartDomain do
         end
 
         it 'should modify the domain' do
-          expect(libvirt_domain).to receive(:undefine)
+          expect(ui).to_not receive(:error)
           expect(logger).to receive(:debug).with('tpm config changed')
-          expect(servers).to receive(:create).with(xml: updated_domain_xml)
+          expect(connection).to receive(:define_domain).with(updated_domain_xml).and_return(libvirt_domain)
+          expect(libvirt_domain).to receive(:xml_desc).and_return(domain_xml, updated_domain_xml)
           expect(libvirt_domain).to receive(:autostart=)
           expect(domain).to receive(:start)
 
@@ -235,8 +270,9 @@ describe VagrantPlugins::ProviderLibvirt::Action::StartDomain do
         end
 
         it 'should not modify the domain' do
+          expect(ui).to_not receive(:error)
           expect(logger).to_not receive(:debug).with('clock timers config changed')
-          expect(servers).to_not receive(:create)
+          expect(connection).to_not receive(:define_domain)
           expect(libvirt_domain).to receive(:autostart=)
           expect(domain).to receive(:start)
 
@@ -252,10 +288,13 @@ describe VagrantPlugins::ProviderLibvirt::Action::StartDomain do
           EOF
         end
 
+        let(:updated_test_file) { 'clock_timer_rtc_tsc.xml' }
+
         it 'should modify the domain' do
-          expect(libvirt_domain).to receive(:undefine)
+          expect(ui).to_not receive(:error)
           expect(logger).to receive(:debug).with('clock timers config changed')
-          expect(servers).to receive(:create).with(xml: match(/<clock offset='utc'>\s*<timer name='rtc'\/>\s*<timer name='tsc'\/>\s*<\/clock>/))
+          expect(connection).to receive(:define_domain).with(match(/<clock offset='utc'>\s*<timer name='rtc'\/>\s*<timer name='tsc'\/>\s*<\/clock>/)).and_return(libvirt_domain)
+          expect(libvirt_domain).to receive(:xml_desc).and_return(domain_xml, updated_domain_xml)
           expect(libvirt_domain).to receive(:autostart=)
           expect(domain).to receive(:start)
 
@@ -264,10 +303,13 @@ describe VagrantPlugins::ProviderLibvirt::Action::StartDomain do
       end
 
       context 'timers removed' do
+        let(:updated_test_file) { 'clock_timer_removed.xml' }
+
         it 'should modify the domain' do
-          expect(libvirt_domain).to receive(:undefine)
+          expect(ui).to_not receive(:error)
           expect(logger).to receive(:debug).with('clock timers config changed')
-          expect(servers).to receive(:create).with(xml: match(/<clock offset='utc'>\s*<\/clock>/))
+          expect(connection).to receive(:define_domain).with(match(/<clock offset='utc'>\s*<\/clock>/)).and_return(libvirt_domain)
+          expect(libvirt_domain).to receive(:xml_desc).and_return(domain_xml, updated_domain_xml)
           expect(libvirt_domain).to receive(:autostart=)
           expect(domain).to receive(:start)
 
diff --git a/spec/unit/action/start_domain_spec/clock_timer_removed.xml b/spec/unit/action/start_domain_spec/clock_timer_removed.xml
new file mode 100644
index 0000000..051e61a
--- /dev/null
+++ b/spec/unit/action/start_domain_spec/clock_timer_removed.xml
@@ -0,0 +1,38 @@
+<domain xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0' type=''>
+  <name/>
+  <title/>
+  <description/>
+  <uuid/>
+  <memory/>
+  <vcpu>1</vcpu>
+  <cpu mode='host-model'>
+    <model fallback='allow'/>
+  </cpu>
+  <os>
+    <type>hvm</type>
+    <kernel/>
+    <initrd/>
+    <cmdline/>
+  </os>
+  <features>
+    <acpi/>
+    <apic/>
+    <pae/>
+  </features>
+  <clock offset='utc'>
+    
+  </clock>
+  <devices>
+    <serial type='pty'>
+      <target port='0'/>
+    </serial>
+    <console type='pty'>
+      <target port='0'/>
+    </console>
+    <input bus='ps2' type='mouse'/>
+    <graphics autoport='yes' keymap='en-us' listen='127.0.0.1' port='-1' type='vnc'/>
+    <video>
+      <model heads='1' type='cirrus' vram='16384'/>
+    </video>
+  </devices>
+</domain>
diff --git a/spec/unit/action/start_domain_spec/clock_timer_rtc_tsc.xml b/spec/unit/action/start_domain_spec/clock_timer_rtc_tsc.xml
new file mode 100644
index 0000000..206f6d0
--- /dev/null
+++ b/spec/unit/action/start_domain_spec/clock_timer_rtc_tsc.xml
@@ -0,0 +1,39 @@
+<domain xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0' type=''>
+  <name/>
+  <title/>
+  <description/>
+  <uuid/>
+  <memory/>
+  <vcpu>1</vcpu>
+  <cpu mode='host-model'>
+    <model fallback='allow'/>
+  </cpu>
+  <os>
+    <type>hvm</type>
+    <kernel/>
+    <initrd/>
+    <cmdline/>
+  </os>
+  <features>
+    <acpi/>
+    <apic/>
+    <pae/>
+  </features>
+  <clock offset='utc'>
+    <timer name='rtc'/>
+    <timer name='tsc'/>
+  </clock>
+  <devices>
+    <serial type='pty'>
+      <target port='0'/>
+    </serial>
+    <console type='pty'>
+      <target port='0'/>
+    </console>
+    <input bus='ps2' type='mouse'/>
+    <graphics autoport='yes' keymap='en-us' listen='127.0.0.1' port='-1' type='vnc'/>
+    <video>
+      <model heads='1' type='cirrus' vram='16384'/>
+    </video>
+  </devices>
+</domain>
diff --git a/spec/unit/action/start_domain_spec/nvram_domain_other_setting.xml b/spec/unit/action/start_domain_spec/nvram_domain_other_setting.xml
index 9b80562..3aeccfd 100644
--- a/spec/unit/action/start_domain_spec/nvram_domain_other_setting.xml
+++ b/spec/unit/action/start_domain_spec/nvram_domain_other_setting.xml
@@ -4,11 +4,11 @@
   <description>Source: /home/test/vagrant-libvirt/Vagrantfile</description>
   <memory unit='KiB'>2097152</memory>
   <currentMemory unit='KiB'>2097152</currentMemory>
-  <vcpu placement='static'>4</vcpu>
+  <vcpu placement='static'>2</vcpu>
   <os>
     <type arch='x86_64' machine='pc-i440fx-6.0'>hvm</type>
     <loader type='pflash'>/path/to/loader/file</loader>
-    <nvram>/path/to/nvram/file</nvram>
+    <nvram>/path/to/nvram/file1</nvram>
     <boot dev='hd'/>
   </os>
   <features>
diff --git a/vagrant-libvirt.gemspec b/vagrant-libvirt.gemspec
index 07eac93..5e1abb5 100644
--- a/vagrant-libvirt.gemspec
+++ b/vagrant-libvirt.gemspec
@@ -27,6 +27,7 @@ Gem::Specification.new do |s|
   s.add_runtime_dependency 'fog-libvirt', '>= 0.6.0'
   s.add_runtime_dependency 'fog-core', '~> 2'
   s.add_runtime_dependency 'rexml'
+  s.add_runtime_dependency 'diffy'
 
   # Make sure to allow use of the same version as Vagrant by being less specific
   s.add_runtime_dependency 'nokogiri', '~> 1.6'