diff --git a/library/centos/roles/kvm/defaults/main.yml b/library/centos/roles/kvm/defaults/main.yml
index f36e65e5..ef058002 100644
--- a/library/centos/roles/kvm/defaults/main.yml
+++ b/library/centos/roles/kvm/defaults/main.yml
@@ -13,10 +13,8 @@ virtualization_centos6_packages:
 virtualization_centos_netinst_url: "http://mi.mirror.garr.it/mirrors/CentOS/7/os/x86_64/"
 virtualization_os_boot_dir: /var/lib/libvirt/boot
 virtualization_os_boot_images:
-  - "http://mi.mirror.garr.it/mirrors/CentOS/7.0.1406/isos/x86_64/CentOS-7.0-1406-x86_64-Minimal.iso"
-  - "http://mi.mirror.garr.it/mirrors/CentOS/5.11/isos/x86_64/CentOS-5.11-x86_64-netinstall.iso"
-  - "http://cdimage.debian.org/debian-cd/7.7.0/amd64/iso-cd/debian-7.7.0-amd64-netinst.iso"
-  - "http://releases.ubuntu.com/14.04.1/ubuntu-14.04.1-server-amd64.iso"
+  - "http://centos.mirror.garr.it/centos/7.7.1908/isos/x86_64/CentOS-7-x86_64-Minimal-1908.iso"
+  - "http://releases.ubuntu.com/bionic/ubuntu-18.04.3-live-server-amd64.iso"
 
 virtualization_activate_forwarding: True
 
diff --git a/library/centos/roles/kvm/tasks/main.yml b/library/centos/roles/kvm/tasks/main.yml
index 6cc5073d..607f31ce 100644
--- a/library/centos/roles/kvm/tasks/main.yml
+++ b/library/centos/roles/kvm/tasks/main.yml
@@ -1,47 +1,46 @@
 ---
 - name: Install the virtualization packages
-  yum: name={{ item }} state={{ virtualization_pkg_state }}
-  with_items: virtualization_packages
+  yum: name={{ virtualization_packages }} state={{ virtualization_pkg_state }}
   tags: kvm
 
 - name: Enable libvirtd when needed
   service: name={{ item }} state=started enabled=yes
-  with_items: virtualization_services_to_be_enabled
-  when: virtualization_enable_libvirtd
+  with_items: '{{ virtualization_services_to_be_enabled }}'
+  when: virtualization_enable_libvirtd | bool
   tags: [ 'kvm', 'libvirt' ]
     
 - name: Disable nfs
   service: name={{ item }} state=stopped enabled=no
-  with_items: virtualization_nfs_services_to_be_disabled
-  when: virtualization_disable_nfs
+  with_items: '{{ virtualization_nfs_services_to_be_disabled }}'
+  when: virtualization_disable_nfs | bool
   tags: [ 'kvm', 'nfs' ]
     
 - name: Disable iscsi
   service: name={{ item }} state=stopped enabled=no
-  with_items: virtualization_iscsi_services_to_be_disabled
-  when: virtualization_disable_iscsi
+  with_items: '{{ virtualization_iscsi_services_to_be_disabled }}'
+  when: virtualization_disable_iscsi | bool
   tags: [ 'kvm' , 'iscsi' ]
     
 - name: Set some kernel parameters needed by virtualization. IP forwarding for example, if we need NAT
   sysctl: name={{ item.name }} state={{ item.state }} value={{ item.value }} sysctl_file=/etc/sysctl.d/90-virtualization.conf reload=yes sysctl_set=yes
-  with_items: virtualization_sysctl_tuning
+  with_items: '{{ virtualization_sysctl_tuning }}'
   tags: kvm
 
 - name: Collect the ISO boot images
   get_url: url="{{ item }}" dest={{ virtualization_os_boot_dir }}/
-  with_items: virtualization_os_boot_images
+  with_items: '{{ virtualization_os_boot_images }}'
   tags: [ 'kvm', 'iso_images' ]
 
 - name: Create the LVM PV
   command: pvcreate {{ item }}
-  with_items: virtualization_kvm_lvm_pv
-  when: virtualization_kvm_create_lvm_pv
+  with_items: '{{ virtualization_kvm_lvm_pv }}'
+  when: virtualization_kvm_create_lvm_pv | bool
   tags: [ 'kvm', 'lvm_pv' ]
 
 - name: Create the LVM VG to be used by the virtual guests
   lvg: vg={{ virtualization_kvm_lvm_vg }} pvs={{ item }}
-  with_items: virtualization_kvm_lvm_pv
-  when: virtualization_kvm_create_lvm_vg
+  with_items: '{{ virtualization_kvm_lvm_pv }}'
+  when: virtualization_kvm_create_lvm_vg | bool
   tags: [ 'kvm', 'lvm_vg' ]
 
 - name: Fix the /dev/kvm permissions