diff --git a/host_vars/codichotomie.adm.crans.org.yml b/host_vars/codichotomie.adm.crans.org.yml
new file mode 100644
index 00000000..3c3fe54f
--- /dev/null
+++ b/host_vars/codichotomie.adm.crans.org.yml
@@ -0,0 +1,3 @@
+interfaces:
+  adm: eth0
+
diff --git a/hosts b/hosts
index 7ed9d2a5..ea5b0fb1 100644
--- a/hosts
+++ b/hosts
@@ -91,6 +91,7 @@ jack.adm.crans.org
 zephir.adm.crans.org
 
 [crans_vm]
+codichotomie.adm.crans.org
 voyager.adm.crans.org
 #silice.adm.crans.org
 routeur-sam.adm.crans.org
diff --git a/plays/network-interfaces.yml b/plays/network-interfaces.yml
index 76baadb6..66b4c9a2 100755
--- a/plays/network-interfaces.yml
+++ b/plays/network-interfaces.yml
@@ -1,6 +1,6 @@
 #!/usr/bin/env ansible-playbook
 ---
-- hosts: voyager.adm.crans.org,boeing.adm.crans.org,fluxx.adm.crans.org,hodaur.adm.crans.org,unifi.adm.crans.org,kiwi.adm.crans.org,roundcube.adm.crans.org,monitoring.adm.crans.org,bigbluebutton.adm.crans.org
+- hosts: voyager.adm.crans.org,boeing.adm.crans.org,fluxx.adm.crans.org,hodaur.adm.crans.org,unifi.adm.crans.org,kiwi.adm.crans.org,roundcube.adm.crans.org,monitoring.adm.crans.org,bigbluebutton.adm.crans.org,codichotomie.adm.crans.org
   vars:
     vlan:
       - name: srv
diff --git a/roles/debian-apt-sources/templates/apt/sources.list.j2 b/roles/debian-apt-sources/templates/apt/sources.list.j2
index dde04587..8eb3d432 100644
--- a/roles/debian-apt-sources/templates/apt/sources.list.j2
+++ b/roles/debian-apt-sources/templates/apt/sources.list.j2
@@ -1,9 +1,12 @@
 {{ ansible_header | comment }}
 
 {% if ansible_lsb.id == "Debian" %}
+{% if ansible_lsb.codename != "bullseye" %}
+{# Debian security does not exist yet for bullseye #}
 # Mises à jour de sécurité
 deb     {{ debian_mirror }}-security {{ ansible_lsb.codename }}/updates {{ debian_components }}
 
+{% endif %}
 # Dépôt classique
 deb     {{ debian_mirror }} {{ ansible_lsb.codename }} {{ debian_components }}
 
diff --git a/roles/nullmailer/tasks/main.yml b/roles/nullmailer/tasks/main.yml
index 21699041..21d2d875 100644
--- a/roles/nullmailer/tasks/main.yml
+++ b/roles/nullmailer/tasks/main.yml
@@ -13,13 +13,16 @@
   copy:
     content: "{{ mail_smtp_server }} smtp\n"
     dest: /etc/nullmailer/remotes
+    mode: 0644
 
 - name: Set nullmailer adminaddr
   copy:
     content: "{{ mail_root }}\n"
     dest: /etc/nullmailer/adminaddr
+    mode: 0644
 
 - name: Set nullmailer defaulthost
   copy:
     content: "{{ mail_defaulthost }}\n"
     dest: /etc/nullmailer/defaulthost
+    mode: 0644