diff --git a/share/doc/xsd/host.xsd b/share/doc/xsd/host.xsd
index 437c0cf3e5..2d85b5c465 100644
--- a/share/doc/xsd/host.xsd
+++ b/share/doc/xsd/host.xsd
@@ -42,11 +42,8 @@
               <xs:element name="VMS_THREAD" type="xs:integer"/>
               <xs:element name="DATASTORES">
                 <xs:complexType>
-                    <xs:all>
+                    <xs:sequence>
                       <xs:element name="DISK_USAGE" type="xs:integer"/>
-                      <xs:element name="FREE_DISK" type="xs:integer"/>
-                      <xs:element name="MAX_DISK" type="xs:integer"/>
-                      <xs:element name="USED_DISK" type="xs:integer"/>
                       <xs:element name="DS" minOccurs="0" maxOccurs="unbounded">
                         <xs:complexType>
                           <xs:sequence>
@@ -60,7 +57,10 @@
                           </xs:sequence>
                         </xs:complexType>
                       </xs:element>
-                    </xs:all>
+                      <xs:element name="FREE_DISK" type="xs:integer"/>
+                      <xs:element name="MAX_DISK" type="xs:integer"/>
+                      <xs:element name="USED_DISK" type="xs:integer"/>
+                    </xs:sequence>
                 </xs:complexType>
               </xs:element>
               <xs:element name="PCI_DEVICES">
diff --git a/share/linters/.rubocop.yml b/share/linters/.rubocop.yml
index 0e0ebff8e3..da71647c4f 100644
--- a/share/linters/.rubocop.yml
+++ b/share/linters/.rubocop.yml
@@ -507,6 +507,10 @@ AllCops:
     - src/oca/ruby/opennebula/flow/grammar.rb
     - src/oca/ruby/opennebula/flow/validator.rb
     - src/sunstone/OpenNebulaVMRC.rb
+    - src/oneprovision/lib/provision/provision_config.rb
+    - src/vmm_mad/remotes/lib/vcenter_driver/datastore.rb
+    - src/vmm_mad/remotes/lib/vcenter_driver/virtual_machine.rb
+    - src/vmm_mad/remotes/lib/vcenter_driver/virtual_machine.rb
   NewCops: enable
 
 ########
diff --git a/src/mad/ruby/DriverExecHelper.rb b/src/mad/ruby/DriverExecHelper.rb
index 8d31177fd1..b2eb09a160 100644
--- a/src/mad/ruby/DriverExecHelper.rb
+++ b/src/mad/ruby/DriverExecHelper.rb
@@ -68,9 +68,7 @@ module DriverExecHelper
     # @param [String, nil] default_name alternative name for the script
     # @param [String, ''] directory to append to the scripts path for actions
     # @return [String] command line needed to execute the action
-    def action_command_line(action, parameters,
-                            default_name = nil, directory = '')
-
+    def action_command_line(action, parameters, default_name = nil, directory = '')
         if action.is_a?(String) && action[0] == '/'
             return action + ' ' + parameters if parameters
 
@@ -111,9 +109,7 @@ module DriverExecHelper
     #
     # Sends a message to the OpenNebula core through stdout
     # rubocop:disable Metrics/ParameterLists
-    def send_message(action = '-', result = RESULT[:failure],
-                     id = '-', info = '-')
-
+    def send_message(action = '-', result = RESULT[:failure], id = '-', info = '-')
         @send_mutex.synchronize do
             STDOUT.puts "#{action} #{result} #{id} #{info}"
             STDOUT.flush
diff --git a/src/oca/ruby/opennebula/flow/service_template_ext.rb b/src/oca/ruby/opennebula/flow/service_template_ext.rb
index 3835fd5d6e..f37e3f8539 100644
--- a/src/oca/ruby/opennebula/flow/service_template_ext.rb
+++ b/src/oca/ruby/opennebula/flow/service_template_ext.rb
@@ -38,7 +38,6 @@ module OpenNebula::ServiceTemplateExt
             # @param market_id [Integer] Marketplace ID to import app
             # @param name      [String]  Service Template App name
             def mp_import(templates, market_id, name)
-                template = ''
                 name   ||= "#{@body['name']}-#{SecureRandom.hex[0..9]}"
 
                 template = <<-EOT
diff --git a/src/oneprovision/lib/provision/ansible.rb b/src/oneprovision/lib/provision/ansible.rb
index e0ffadc785..abd5bc2635 100644
--- a/src/oneprovision/lib/provision/ansible.rb
+++ b/src/oneprovision/lib/provision/ansible.rb
@@ -125,7 +125,6 @@ module OneProvision
             # @param only_hosts [Array] Hostames - limit configure to them
             def configure(hosts, datastores = nil, provision = nil,
                           only_hosts = [])
-
                 return if hosts.nil? || hosts.empty?
 
                 Driver.retry_loop('Failed to configure hosts', provision) do
diff --git a/src/vmm_mad/remotes/lib/vcenter_driver/rest_client.rb b/src/vmm_mad/remotes/lib/vcenter_driver/rest_client.rb
index b261618c96..aa3cb2a88e 100644
--- a/src/vmm_mad/remotes/lib/vcenter_driver/rest_client.rb
+++ b/src/vmm_mad/remotes/lib/vcenter_driver/rest_client.rb
@@ -86,13 +86,7 @@ module VCenterDriver
             new(connection)
         end
 
-        def get_or_create_tag(
-            api_client,
-            category_id,
-            tag_name,
-            tag_description
-        )
-
+        def get_or_create_tag(api_client, category_id, tag_name, tag_description)
             tag_api = VSphereAutomation::CIS::TaggingTagApi.new(api_client)
             tag = tag_api.list.value.find do |id|
                 c = tag_api.get(id).value
diff --git a/src/vmm_mad/remotes/lib/vcenter_driver/vi_client.rb b/src/vmm_mad/remotes/lib/vcenter_driver/vi_client.rb
index 0446d9a1ca..4842957170 100644
--- a/src/vmm_mad/remotes/lib/vcenter_driver/vi_client.rb
+++ b/src/vmm_mad/remotes/lib/vcenter_driver/vi_client.rb
@@ -239,8 +239,8 @@ module VCenterDriver
             begin
                 orig_stderr = $stderr.clone
                 orig_stdout = $stdout.clone
-                $stderr.reopen File.new('/dev/null', 'w')
-                $stdout.reopen File.new('/dev/null', 'w')
+                $stderr.reopen File.new(File::NULL, 'w')
+                $stdout.reopen File.new(File::NULL, 'w')
                 retval = yield
             rescue StandardError => e
                 $stdout.reopen orig_stdout
@@ -256,7 +256,7 @@ module VCenterDriver
         def self.in_stderr_silence
             begin
                 orig_stderr = $stderr.clone
-                $stderr.reopen File.new('/dev/null', 'w')
+                $stderr.reopen File.new(File::NULL, 'w')
                 retval = yield
             rescue StandardError => e
                 $stderr.reopen orig_stderr
diff --git a/src/vmm_mad/remotes/lib/vcenter_driver/vm_template.rb b/src/vmm_mad/remotes/lib/vcenter_driver/vm_template.rb
index 68188aafd1..41d84e24cd 100644
--- a/src/vmm_mad/remotes/lib/vcenter_driver/vm_template.rb
+++ b/src/vmm_mad/remotes/lib/vcenter_driver/vm_template.rb
@@ -1117,12 +1117,7 @@ module VCenterDriver
             one_vn
         end
 
-        def import_vcenter_nics(
-            opts,
-            vm_id = nil,
-            dc_name = nil
-        )
-
+        def import_vcenter_nics(opts, vm_id = nil, dc_name = nil)
             vi_client = opts[:vi_client]
             vc_uuid = opts[:vc_uuid]
             npool = opts[:npool]