diff --git a/roles/common/tasks/freebsd.yml b/roles/common/tasks/freebsd.yml
index 9f20018..78f4739 100644
--- a/roles/common/tasks/freebsd.yml
+++ b/roles/common/tasks/freebsd.yml
@@ -21,7 +21,7 @@
     sysctl:
       - item: net.inet.ip.forwarding
         value: 1
-      - item: net.inet6.ip6.forwarding
+      - item: "{{ 'net.inet6.ip6.forwarding' if ipv6_support else none }}"
         value: 1
   tags:
     - always
diff --git a/roles/common/tasks/main.yml b/roles/common/tasks/main.yml
index 73e6783..21d51a4 100644
--- a/roles/common/tasks/main.yml
+++ b/roles/common/tasks/main.yml
@@ -15,6 +15,7 @@
 
   - name: Sysctl tuning
     sysctl: name="{{ item.item }}" value="{{ item.value }}"
+    when: item.item != ""
     with_items:
       - "{{ sysctl|default([]) }}"
     tags:
diff --git a/roles/common/tasks/ubuntu.yml b/roles/common/tasks/ubuntu.yml
index 9c6e6a5..6dbc633 100644
--- a/roles/common/tasks/ubuntu.yml
+++ b/roles/common/tasks/ubuntu.yml
@@ -114,7 +114,7 @@
         value: 1
       - item: net.ipv4.conf.all.forwarding
         value: 1
-      - item: net.ipv6.conf.all.forwarding
+      - item: "{{ 'net.ipv6.conf.all.forwarding' if ipv6_support else none }}"
         value: 1
   tags:
     - always