diff --git a/defaults/main.yml b/defaults/main.yml
index 5c45f23..c6f87e2 100644
--- a/defaults/main.yml
+++ b/defaults/main.yml
@@ -5,16 +5,32 @@ default_locale_lang: "en_US.UTF-8"
 default_deb_locale_messages: "C.UTF-8"
 default_el_locale_messages: "en_US.UTF-8"
 locales_list:
-  - { name: '{{ default_locale_lang }}' }
-  - { name: 'en_US.UTF-8' }
-  - { name: 'en_US' }
-  - { name: 'it_IT.UTF-8' }
-  - { name: 'it_IT' }
+  - {name: '{{ default_locale_lang }}'}
+  - {name: 'en_US.UTF-8'}
+  - {name: 'en_US'}
+  - {name: 'it_IT.UTF-8'}
+  - {name: 'it_IT'}
 
 domain_name: '{{ ansible_domain }}'
+
+sysctl_custom_file: /etc/sysctl.d/90-custom-values.conf
+sysctl_opts_reload: yes
+sysctl_custom_file_state: present
+
+# Only name and value are mandatory. The others have defaults
+sysctl_custom_options: []
+# - name: 'net.nf_conntrack_max'
+#   value: '32768'
+#   sysctlfile: '{{ sysctl_custom_file }}'
+#   sysctl_reload: '{{ sysctl_opts_reload }}'
+#   sysctlfile_state: '{{ sysctl_custom_file_state }}'
+
+disable_ipv6: false
+ipv6_sysctl_value: 1
+ipv6_sysctl_file: /etc/sysctl.d/10-ipv6-disable.conf
 #
 # Define the following variables to manage additional disks and mount points, even static nfs ones
-additional_disks: False
+additional_disks: false
 disks_and_mountpoints_list: []
 #  - { mountpoint: '/data', device: 'xvda3', fstype: 'xfs', opts: 'noatime', state: 'mounted', create_filesystem: True }
 
@@ -30,7 +46,7 @@ idmap_conf_options:
   - { section: 'General', option: 'Verbosity', value: '{{ idmap_verbosity }}', state: 'present' }
 
 # autofs mount points
-autofs_client_mountpoint: False
+autofs_client_mountpoint: false
 autofs_conf_options:
   - { section: 'autofs', option: 'master_map_name', value: '/etc/auto.master', state: 'present' }
   - { section: 'autofs', option: 'timeout', value: '300', state: 'present' }
diff --git a/tasks/main.yml b/tasks/main.yml
index 90af6a3..cfb2221 100644
--- a/tasks/main.yml
+++ b/tasks/main.yml
@@ -3,6 +3,7 @@
 - import_tasks: hostname.yml
 - import_tasks: locale.yml
 - import_tasks: timezone.yml
+- import_tasks: sysctl.yml
 - import_tasks: http_client_proxy.yml
 - import_tasks: additional_disks.yml
   when: additional_disks
diff --git a/tasks/sysctl.yml b/tasks/sysctl.yml
new file mode 100644
index 0000000..cfbef0e
--- /dev/null
+++ b/tasks/sysctl.yml
@@ -0,0 +1,52 @@
+---
+- block:
+    - name: Ensure that the /etc/sysctl.d directory exists
+      file:
+        path: /etc/sysctl.d
+        state: directory
+        owner: root
+        group: root
+
+  tags: ['sysctl', 'kernel', 'sysctl_ipv6', 'ipv6']
+
+- block:
+    - name: Set the custom sysctl values
+      sysctl:
+        name: '{{ item.name }}'
+        value: '{{ item.value }}'
+        sysctl_file: "{{ item.sysctlfile | default ('/etc/sysctl.d/90-custom-values.conf') }}"
+        reload: "{{ item.sysctl_reload | default(true) }} state={{ item.sysctlfile_state | default('present') }}"
+      loop: '{{ sysctl_custom_options }}'
+
+  tags: ['sysctl', 'kernel']
+
+- block:
+    - name: Disable the in kernel ipv6 support
+      sysctl:
+        name: '{{ item }}'
+        value: 1
+        sysctl_file: '{{ ipv6_sysctl_file }}'
+        reload: true
+        state: present
+      loop:
+        - net.ipv6.conf.all.disable_ipv6
+        - net.ipv6.conf.default.disable_ipv6
+        - net.ipv6.conf.lo.disable_ipv6
+        - net.ipv6.conf.{{ ansible_default_ipv4.interface }}.disable_ipv6
+      when: disable_ipv6
+
+    - name: enable the in kernel ipv6 support
+      sysctl:
+        name: '{{ item }}'
+        value: 0
+        sysctl_file: '{{ ipv6_sysctl_file }}'
+        reload: true
+        state: present
+      loop:
+        - net.ipv6.conf.all.disable_ipv6
+        - net.ipv6.conf.default.disable_ipv6
+        - net.ipv6.conf.lo.disable_ipv6
+        - net.ipv6.conf.{{ ansible_default_ipv4.interface }}.disable_ipv6
+      when: not disable_ipv6
+
+  tags: ['sysctl', 'kernel', 'sysctl_ipv6', 'ipv6']