diff --git a/ldap-client-config/defaults/main.yml b/ldap-client-config/defaults/main.yml
index 048eaa20..8ed59077 100644
--- a/ldap-client-config/defaults/main.yml
+++ b/ldap-client-config/defaults/main.yml
@@ -1,4 +1,4 @@
 ---
-nemis_ldap_uri: "ldap://ldap.sub.research-infrastructures.eu"
-nemis_ldap_base_dn: "dc=research-infrastructures,dc=eu"
-
+ldap_uri: "ldap://ldap.sub.research-infrastructures.eu"
+ldap_base_dn: "dc=research-infrastructures,dc=eu"
+ldap_tls_cacert: /etc/ssl/certs/ca-certificates.crt
diff --git a/ldap-client-config/tasks/main.yml b/ldap-client-config/tasks/main.yml
index 7f5d78bf..c4b4e76e 100644
--- a/ldap-client-config/tasks/main.yml
+++ b/ldap-client-config/tasks/main.yml
@@ -4,36 +4,30 @@
   with_items:
     - ldapscripts
     - libpam-ldap
-  tags:
-    - ldap-client
+  tags: ldap-client
 
 - name: Write the ldap client configuration file
-  template: src=ldap.conf.j2 dest=/etc/ldap.conf mode=444 owner=root group=root
+  template: src=ldap.conf-old.j2 dest=/etc/ldap.conf mode=444 owner=root group=root
   when: is_ubuntu_less_than_trusty
-  tags:
-    - ldap-client
+  tags: ldap-client
 
 - name: Write the ldap client configuration file
   template: src=ldap.conf.j2 dest=/etc/ldap/ldap.conf mode=444 owner=root group=root
   when: is_trusty
-  tags:
-    - ldap-client
+  tags: ldap-client
 
 - name: set the ldapscripts.conf uri
-  action: configfile path=/etc/ldapscripts/ldapscripts.conf key=SERVER value='{{ nemis_ldap_uri }}' syntax=shell
+  action: configfile path=/etc/ldapscripts/ldapscripts.conf key=SERVER value='{{ ldap_uri }}' syntax=shell
   when: is_trusty
-  tags:
-    - ldap-client
+  tags: ldap-client
 
 - name: set the ldapscripts.conf bind dn
-  action: configfile path=/etc/ldapscripts/ldapscripts.conf key=BINDDN value='cn=admin,{{ nemis_ldap_base_dn }}' syntax=shell
+  action: configfile path=/etc/ldapscripts/ldapscripts.conf key=BINDDN value='cn=admin,{{ ldap_base_dn }}' syntax=shell
   when: is_trusty
-  tags:
-    - ldap-client
+  tags: ldap-client
     
 - name: set the ldapscripts.conf dn suffix
-  action: configfile path=/etc/ldapscripts/ldapscripts.conf key=SUFFIX value='{{ nemis_ldap_base_dn }}' syntax=shell
+  action: configfile path=/etc/ldapscripts/ldapscripts.conf key=SUFFIX value='{{ ldap_base_dn }}' syntax=shell
   when: is_trusty
-  tags:
-    - ldap-client
+  tags: ldap-client
     
diff --git a/ldap-client-config/templates/ldap.conf-old.j2 b/ldap-client-config/templates/ldap.conf-old.j2
new file mode 100644
index 00000000..38754476
--- /dev/null
+++ b/ldap-client-config/templates/ldap.conf-old.j2
@@ -0,0 +1,11 @@
+# The distinguished name of the search base.
+BASE {{ ldap_base_dn }}
+
+# Another way to specify your LDAP server is to provide an
+URI {{ ldap_uri }}
+
+# The LDAP version to use (defaults to 3
+# if supported by client library)
+ldap_version 3
+
+nss_initgroups_ignoreusers avahi,backup,bin,daemon,games,gnats,irc,libuuid,list,lp,mail,man,messagebus,munin,news,nslcd,proxy,root,rstudio-server,sshd,sync,sys,syslog,uucp,www-data
diff --git a/ldap-client-config/templates/ldap.conf.j2 b/ldap-client-config/templates/ldap.conf.j2
index 7a81eae4..ae1526d6 100644
--- a/ldap-client-config/templates/ldap.conf.j2
+++ b/ldap-client-config/templates/ldap.conf.j2
@@ -1,11 +1,14 @@
 # The distinguished name of the search base.
-BASE {{ nemis_ldap_base_dn }}
+BASE {{ ldap_base_dn }}
 
 # Another way to specify your LDAP server is to provide an
-URI {{ nemis_ldap_uri }}
+URI {{ ldap_uri }}
 
 # The LDAP version to use (defaults to 3
 # if supported by client library)
 ldap_version 3
 
 nss_initgroups_ignoreusers avahi,backup,bin,daemon,games,gnats,irc,libuuid,list,lp,mail,man,messagebus,munin,news,nslcd,proxy,root,rstudio-server,sshd,sync,sys,syslog,uucp,www-data
+
+# TLS certificates (needed for GnuTLS)
+TLS_CACERT         {{ ldap_tls_cacert }}
diff --git a/ubuntu-deb-general/defaults/main.yml b/ubuntu-deb-general/defaults/main.yml
index 5ebb13bc..140e53c0 100644
--- a/ubuntu-deb-general/defaults/main.yml
+++ b/ubuntu-deb-general/defaults/main.yml
@@ -88,10 +88,12 @@ configure_munin: False
 # Manage the root ssh keys
 manage_root_ssh_keys: False
 
-install_external_ca_files: True
-external_ca_dest_dir: /etc/ssl/certs
-external_ca_list:
-  - { url: "https://security.fi.infn.it/CA/mgt/INFNCA.pem", dest_file: '{{ external_ca_dest_dir }}/infn-ca.pem' }
+install_additional_ca_certs: False
+additional_ca_dest_dir: /usr/local/share/ca-certificates
+# IMPORTANT: the destination file extension must be .crt
+#x509_additional_ca_certs:
+#  - { url: "https://security.fi.infn.it/CA/mgt/INFNCA.pem", dest_file: '{{ additional_ca_dest_dir }}/infn-ca.crt' }
+
 #
 # debian/ubuntu distributions controllers
 #
diff --git a/ubuntu-deb-general/handlers/main.yml b/ubuntu-deb-general/handlers/main.yml
index cbb26546..fb906757 100644
--- a/ubuntu-deb-general/handlers/main.yml
+++ b/ubuntu-deb-general/handlers/main.yml
@@ -18,3 +18,7 @@
 - name: Restart rsyslog
   service: name=rsyslog state=restarted
 
+- name: Update the CA bundle list
+  shell: update-ca-certificates
+  tags: ca
+
diff --git a/ubuntu-deb-general/tasks/install_external_ca_cert.yml b/ubuntu-deb-general/tasks/install_external_ca_cert.yml
index c90d7752..0be2a9e4 100644
--- a/ubuntu-deb-general/tasks/install_external_ca_cert.yml
+++ b/ubuntu-deb-general/tasks/install_external_ca_cert.yml
@@ -1,7 +1,8 @@
 ---
-- name: Install the INFN CA certificate
+- name: Install the additional CA certificates
   get_url: url={{ item.url }} dest={{ item.dest_file }}
-  with_items: external_ca_list
-  when: install_external_ca_files
+  with_items: x509_additional_ca_certs
+  when: install_additional_ca_certs
+  notify: Update the CA bundle list
   tags: ca