diff --git a/CHANGELOG.md b/CHANGELOG.md
index a03d0c98..06abf68b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,19 +12,33 @@ The **patch** part changes incrementally at each release.
 
 ### Added
 
+* Preliminary support for Debian 11 « Bullseye »
+* apache: new variable for mpm mode (+ updated default config accordingly)
 * certbot: add script for manual deploy hooks execution
 * listupgrade: crontab is configurable
+* mongodb: create munin plugins directory if missing
+* redis: instance service for Debian 11
 
 ### Changed
 
+* Use python3 modules for Debian 11 and later
+* elasticsearch: 7.x by default
+* evolinux-base: force Debian version to buster for Evolix repository (temporary)
+* kibana: 7.x by default
 * listupgrade: upstream release 21.06.3
+* mysql: mariadb-client-10.5 on Debian 11
+* mysql: use python3 with Debian 11 and later
 * squid: improve default whitelist (more specific patterns)
+* squid: must be started in foreground mode for systemd
+* squid: remove obsolete variable on Squid 4
 ### Fixed
 
 * certbot: sync_remote excludes itself
 
 ### Removed
 
+* php: remove php-gettext for 7.4
+
 ### Security
 
 ## [10.6.0] 2021-06-28
diff --git a/apache/tasks/server_status.yml b/apache/tasks/server_status.yml
index 2ca77951..efd2b00e 100644
--- a/apache/tasks/server_status.yml
+++ b/apache/tasks/server_status.yml
@@ -33,6 +33,7 @@
 
 - debug:
     var: apache_serverstatus_suffix
+    verbosity: 1
 
 - name: replace server-status suffix in default site index
   replace:
diff --git a/apt/files/bullseye_backports_preferences b/apt/files/bullseye_backports_preferences
new file mode 100644
index 00000000..3a667c93
--- /dev/null
+++ b/apt/files/bullseye_backports_preferences
@@ -0,0 +1,3 @@
+Package: *
+Pin: release a=bullseye-backports
+Pin-Priority: 50
diff --git a/apt/tasks/basics.yml b/apt/tasks/basics.yml
index fee1430a..33c79129 100644
--- a/apt/tasks/basics.yml
+++ b/apt/tasks/basics.yml
@@ -19,6 +19,7 @@
     - /etc/apt/sources.list.d/debian-jessie.list
     - /etc/apt/sources.list.d/debian-stretch.list
     - /etc/apt/sources.list.d/debian-buster.list
+    - /etc/apt/sources.list.d/debian-bullseye.list
     - /etc/apt/sources.list.d/debian-update.list
   when: apt_clean_gandi_sourceslist | bool
   tags:
diff --git a/apt/templates/bullseye_backports.list.j2 b/apt/templates/bullseye_backports.list.j2
new file mode 100644
index 00000000..ab989dec
--- /dev/null
+++ b/apt/templates/bullseye_backports.list.j2
@@ -0,0 +1,3 @@
+# {{ ansible_managed }}
+
+deb http://mirror.evolix.org/debian bullseye-backports {{ apt_backports_components | mandatory }}
diff --git a/apt/templates/bullseye_basics.list.j2 b/apt/templates/bullseye_basics.list.j2
new file mode 100644
index 00000000..5e0a0a53
--- /dev/null
+++ b/apt/templates/bullseye_basics.list.j2
@@ -0,0 +1,5 @@
+# {{ ansible_managed }}
+
+deb http://mirror.evolix.org/debian bullseye {{ apt_basics_components | mandatory }}
+deb http://mirror.evolix.org/debian/ bullseye-updates {{ apt_basics_components | mandatory }}
+deb http://security.debian.org/ bullseye-security {{ apt_basics_components | mandatory }}
diff --git a/apt/templates/evolix_public.list.j2 b/apt/templates/evolix_public.list.j2
index 06de99c0..25156cd0 100644
--- a/apt/templates/evolix_public.list.j2
+++ b/apt/templates/evolix_public.list.j2
@@ -1,3 +1,8 @@
 # {{ ansible_managed }}
 
+{% if ansible_distribution_release == 'bullseye' %}
+# Force previous Debian version (temporary)
+deb http://pub.evolix.net/ buster/
+{% else  %}
 deb http://pub.evolix.net/ {{ ansible_distribution_release }}/
+{% endif  %}
diff --git a/bullseye-detect/tasks/main.yml b/bullseye-detect/tasks/main.yml
new file mode 100644
index 00000000..6f97db0a
--- /dev/null
+++ b/bullseye-detect/tasks/main.yml
@@ -0,0 +1,8 @@
+---
+
+# Force facts until Debian 11 is released because Ansible is dumb
+- set_fact:
+    ansible_distribution_major_version: 11
+    ansible_distribution: "Debian"
+    ansible_distribution_release: "bullseye"
+  when: "ansible_lsb.codename == 'bullseye' or ansible_lsb.release == 'testing/unstable'"
\ No newline at end of file
diff --git a/docker-host/tasks/main.yml b/docker-host/tasks/main.yml
index d3a41a28..796c800d 100644
--- a/docker-host/tasks/main.yml
+++ b/docker-host/tasks/main.yml
@@ -40,9 +40,20 @@
   apt:
     name:
       - docker-ce
-      - python-docker
     update_cache: yes
 
+- name: python-docker is installed
+  apt:
+    name: python-docker
+    state: present
+  when: ansible_distribution_major_version is version('10', '<=')
+
+- name: python3-docker is installed
+  apt:
+    name: python3-docker
+    state: present
+  when: ansible_distribution_major_version is version('10', '>')
+
 - name: Copy Docker daemon configuration file
   template:
     src: daemon.json.j2
diff --git a/elasticsearch/defaults/main.yml b/elasticsearch/defaults/main.yml
index eb254807..2b891953 100644
--- a/elasticsearch/defaults/main.yml
+++ b/elasticsearch/defaults/main.yml
@@ -1,5 +1,5 @@
 ---
-elastic_stack_version: "6.x"
+elastic_stack_version: "7.x"
 
 elasticsearch_cluster_name: Null
 elasticsearch_cluster_members: Null
diff --git a/elasticsearch/files/elastic.gpg b/elasticsearch/files/elastic.gpg
new file mode 100644
index 00000000..2508ddc9
Binary files /dev/null and b/elasticsearch/files/elastic.gpg differ
diff --git a/elasticsearch/tasks/packages.yml b/elasticsearch/tasks/packages.yml
index da154593..b1291d4a 100644
--- a/elasticsearch/tasks/packages.yml
+++ b/elasticsearch/tasks/packages.yml
@@ -52,4 +52,4 @@
     name: elasticsearch
     enabled: yes
   tags:
-  - elasticsearch
+    - elasticsearch
diff --git a/evolinux-base/meta/main.yml b/evolinux-base/meta/main.yml
index 84c001c1..83ed8538 100644
--- a/evolinux-base/meta/main.yml
+++ b/evolinux-base/meta/main.yml
@@ -14,6 +14,7 @@ galaxy_info:
         - jessie
         - stretch
         - buster
+        - bullseye
 
   galaxy_tags: []
     # List tags for your role here, one per line. A tag is
diff --git a/evolinux-base/tasks/kernel.yml b/evolinux-base/tasks/kernel.yml
index 76965f47..b49968f1 100644
--- a/evolinux-base/tasks/kernel.yml
+++ b/evolinux-base/tasks/kernel.yml
@@ -26,7 +26,7 @@
 - name: Disable net.ipv4.tcp_timestamps
   sysctl:
     name: net.ipv4.tcp_timestamps
-    value: 0
+    value: '0'
     sysctl_file: "{{ evolinux_kernel_sysctl_path }}"
     state: present
     reload: yes
diff --git a/evolinux-base/tasks/system.yml b/evolinux-base/tasks/system.yml
index 53fa243c..554bb02a 100644
--- a/evolinux-base/tasks/system.yml
+++ b/evolinux-base/tasks/system.yml
@@ -153,7 +153,7 @@
 
 
 
-- name: Install alert5 init script (buster)
+- name: Install alert5 init script (buster and later)
   template:
     src: system/alert5.sh.j2
     dest: /usr/share/scripts/alert5.sh
@@ -163,7 +163,7 @@
     - evolinux_system_alert5_init | bool
     - ansible_distribution_major_version is version('10', '>=')
 
-- name: Install alert5 service (buster)
+- name: Install alert5 service (buster and later)
   copy:
     src: alert5.service
     dest: /etc/systemd/system/alert5.service
@@ -173,7 +173,7 @@
     - evolinux_system_alert5_init | bool
     - ansible_distribution_major_version is version('10', '>=')
 
-- name: Enable alert5 init script (buster)
+- name: Enable alert5 init script (buster and later)
   systemd:
     name: alert5
     daemon_reload: yes
diff --git a/haproxy/defaults/main.yml b/haproxy/defaults/main.yml
index b94d2872..0745f1a9 100644
--- a/haproxy/defaults/main.yml
+++ b/haproxy/defaults/main.yml
@@ -34,3 +34,4 @@ haproxy_deny_ips: []
 
 haproxy_backports_packages_stretch: haproxy libssl1.0.0
 haproxy_backports_packages_buster: haproxy
+haproxy_backports_packages_bullseye: haproxy
diff --git a/haproxy/tasks/packages_backports.yml b/haproxy/tasks/packages_backports.yml
index 9a682120..eab4fbca 100644
--- a/haproxy/tasks/packages_backports.yml
+++ b/haproxy/tasks/packages_backports.yml
@@ -15,6 +15,10 @@
     haproxy_backports_packages: "{{ haproxy_backports_packages_buster }}"
   when: ansible_distribution_release == 'buster'
 
+- set_fact:
+    haproxy_backports_packages: "{{ haproxy_backports_packages_bullseye }}"
+  when: ansible_distribution_release == 'bullseye'
+
 - name: Prefer HAProxy package from backports
   template:
     src: haproxy_apt_preferences.j2
diff --git a/kibana/defaults/main.yml b/kibana/defaults/main.yml
index e167c21f..7107398c 100644
--- a/kibana/defaults/main.yml
+++ b/kibana/defaults/main.yml
@@ -1,5 +1,5 @@
 ---
-elastic_stack_version: "5.x"
+elastic_stack_version: "7.x"
 
 kibana_server_host: "127.0.0.1"
 kibana_server_basepath: ""
diff --git a/kibana/files/elastic.gpg b/kibana/files/elastic.gpg
new file mode 100644
index 00000000..2508ddc9
Binary files /dev/null and b/kibana/files/elastic.gpg differ
diff --git a/kibana/files/elasticsearch.key b/kibana/files/elasticsearch.key
deleted file mode 100644
index 1b50dcca..00000000
--- a/kibana/files/elasticsearch.key
+++ /dev/null
@@ -1,31 +0,0 @@
------BEGIN PGP PUBLIC KEY BLOCK-----
-Version: GnuPG v2.0.14 (GNU/Linux)
-
-mQENBFI3HsoBCADXDtbNJnxbPqB1vDNtCsqhe49vFYsZN9IOZsZXgp7aHjh6CJBD
-A+bGFOwyhbd7at35jQjWAw1O3cfYsKAmFy+Ar3LHCMkV3oZspJACTIgCrwnkic/9
-CUliQe324qvObU2QRtP4Fl0zWcfb/S8UYzWXWIFuJqMvE9MaRY1bwUBvzoqavLGZ
-j3SF1SPO+TB5QrHkrQHBsmX+Jda6d4Ylt8/t6CvMwgQNlrlzIO9WT+YN6zS+sqHd
-1YK/aY5qhoLNhp9G/HxhcSVCkLq8SStj1ZZ1S9juBPoXV1ZWNbxFNGwOh/NYGldD
-2kmBf3YgCqeLzHahsAEpvAm8TBa7Q9W21C8vABEBAAG0RUVsYXN0aWNzZWFyY2gg
-KEVsYXN0aWNzZWFyY2ggU2lnbmluZyBLZXkpIDxkZXZfb3BzQGVsYXN0aWNzZWFy
-Y2gub3JnPokBOAQTAQIAIgUCUjceygIbAwYLCQgHAwIGFQgCCQoLBBYCAwECHgEC
-F4AACgkQ0n1mbNiOQrRzjAgAlTUQ1mgo3nK6BGXbj4XAJvuZDG0HILiUt+pPnz75
-nsf0NWhqR4yGFlmpuctgCmTD+HzYtV9fp9qW/bwVuJCNtKXk3sdzYABY+Yl0Cez/
-7C2GuGCOlbn0luCNT9BxJnh4mC9h/cKI3y5jvZ7wavwe41teqG14V+EoFSn3NPKm
-TxcDTFrV7SmVPxCBcQze00cJhprKxkuZMPPVqpBS+JfDQtzUQD/LSFfhHj9eD+Xe
-8d7sw+XvxB2aN4gnTlRzjL1nTRp0h2/IOGkqYfIG9rWmSLNlxhB2t+c0RsjdGM4/
-eRlPWylFbVMc5pmDpItrkWSnzBfkmXL3vO2X3WvwmSFiQbkBDQRSNx7KAQgA5JUl
-zcMW5/cuyZR8alSacKqhSbvoSqqbzHKcUQZmlzNMKGTABFG1yRx9r+wa/fvqP6OT
-RzRDvVS/cycws8YX7Ddum7x8uI95b9ye1/Xy5noPEm8cD+hplnpU+PBQZJ5XJ2I+
-1l9Nixx47wPGXeClLqcdn0ayd+v+Rwf3/XUJrvccG2YZUiQ4jWZkoxsA07xx7Bj+
-Lt8/FKG7sHRFvePFU0ZS6JFx9GJqjSBbHRRkam+4emW3uWgVfZxuwcUCn1ayNgRt
-KiFv9jQrg2TIWEvzYx9tywTCxc+FFMWAlbCzi+m4WD+QUWWfDQ009U/WM0ks0Kww
-EwSk/UDuToxGnKU2dQARAQABiQEfBBgBAgAJBQJSNx7KAhsMAAoJENJ9ZmzYjkK0
-c3MIAIE9hAR20mqJWLcsxLtrRs6uNF1VrpB+4n/55QU7oxA1iVBO6IFu4qgsF12J
-TavnJ5MLaETlggXY+zDef9syTPXoQctpzcaNVDmedwo1SiL03uMoblOvWpMR/Y0j
-6rm7IgrMWUDXDPvoPGjMl2q1iTeyHkMZEyUJ8SKsaHh4jV9wp9KmC8C+9CwMukL7
-vM5w8cgvJoAwsp3Fn59AxWthN3XJYcnMfStkIuWgR7U2r+a210W6vnUxU4oN0PmM
-cursYPyeV0NX/KQeUeNMwGTFB6QHS/anRaGQewijkrYYoTNtfllxIu9XYmiBERQ/
-qPDlGRlOgVTd9xUfHFkzB52c70E=
-=92oX
------END PGP PUBLIC KEY BLOCK-----
diff --git a/kibana/tasks/main.yml b/kibana/tasks/main.yml
index 1ed342e0..8ebbe752 100644
--- a/kibana/tasks/main.yml
+++ b/kibana/tasks/main.yml
@@ -129,3 +129,5 @@
 
 - include: proxy_nginx.yml
   when: kibana_proxy_nginx | bool
+  tags:
+    - kibana
diff --git a/lxc-php/defaults/main.yml b/lxc-php/defaults/main.yml
index 1cceab35..ce8a935d 100644
--- a/lxc-php/defaults/main.yml
+++ b/lxc-php/defaults/main.yml
@@ -18,4 +18,4 @@ lxc_php_container_releases:
   php56: "jessie"
   php70: "stretch"
   php73: "buster"
-  php74: "buster"
+  php74: "bullseye"
diff --git a/lxc-php/tasks/php74.yml b/lxc-php/tasks/php74.yml
index 2c4538e8..9438dcc7 100644
--- a/lxc-php/tasks/php74.yml
+++ b/lxc-php/tasks/php74.yml
@@ -13,8 +13,8 @@
     create: yes
     mode: "0644"
   loop:
-    - "deb https://packages.sury.org/php/ buster main"
-    - "deb http://pub.evolix.net/ buster-php74/"
+    - "deb https://packages.sury.org/php/ bullseye main"
+    - "deb http://pub.evolix.net/ bullseye-php74/"
 
 - name: copy pub.evolix.net GPG key
   copy:
@@ -40,7 +40,7 @@
 - name: "{{ lxc_php_version }} - Install PHP packages"
   lxc_container:
     name: "{{ lxc_php_version }}"
-    container_command: "DEBIAN_FRONTEND=noninteractive apt install -y php-fpm php-cli php-gd php-intl php-imap php-ldap php-mysql php-pgsql php-sqlite3 php-gettext php-curl php-zip php-mbstring php-zip composer libphp-phpmailer"
+    container_command: "DEBIAN_FRONTEND=noninteractive apt install -y php-fpm php-cli php-gd php-intl php-imap php-ldap php-mysql php-pgsql php-sqlite3 php-curl php-zip php-mbstring php-zip composer libphp-phpmailer"
 
 - name: "{{ lxc_php_version }} - Copy evolinux PHP configuration"
   template:
diff --git a/lxc/tasks/main.yml b/lxc/tasks/main.yml
index a3a31cf5..74ba69ae 100644
--- a/lxc/tasks/main.yml
+++ b/lxc/tasks/main.yml
@@ -5,7 +5,18 @@
       - lxc
       - debootstrap
       - xz-utils
-      - python-lxc
+
+- name: python-lxc is installed
+  apt:
+    name: python-lxc
+    state: present
+  when: ansible_distribution_major_version is version('10', '<=')
+
+- name: python3-lxc is installed
+  apt:
+    name: python3-lxc
+    state: present
+  when: ansible_distribution_major_version is version('10', '>')
 
 - name: Install additional packages on Buster
   apt:
diff --git a/metricbeat/tasks/main.yml b/metricbeat/tasks/main.yml
index 640a8902..ded5d008 100644
--- a/metricbeat/tasks/main.yml
+++ b/metricbeat/tasks/main.yml
@@ -121,13 +121,13 @@
       src: "{{ item }}"
       dest: /etc/metricbeat/metricbeat.yml
       force: "{{ metricbeat_force_config }}"
-  loop: "{{ query('first_found', templates) }}"
-  vars:
-    templates:
-      - "templates/metricbeat/metricbeat.{{ inventory_hostname }}.yml.j2"
-      - "templates/metricbeat/metricbeat.{{ host_group | default('all') }}.yml.j2"
-      - "templates/metricbeat/metricbeat.default.yml.j2"
-      - "templates/metricbeat.default.yml.j2"
-    notify: restart metricbeat
+    loop: "{{ query('first_found', templates) }}"
+    vars:
+      templates:
+        - "templates/metricbeat/metricbeat.{{ inventory_hostname }}.yml.j2"
+        - "templates/metricbeat/metricbeat.{{ host_group | default('all') }}.yml.j2"
+        - "templates/metricbeat/metricbeat.default.yml.j2"
+        - "templates/metricbeat.default.yml.j2"
+      notify: restart metricbeat
     when: metricbeat_update_config | bool
   when: metricbeat_use_config_template | bool
diff --git a/mongodb/files/server-4.4.asc b/mongodb/files/server-4.4.asc
new file mode 100644
index 00000000..9f4d9161
--- /dev/null
+++ b/mongodb/files/server-4.4.asc
@@ -0,0 +1,30 @@
+-----BEGIN PGP PUBLIC KEY BLOCK-----
+Version: GnuPG v1
+
+mQINBFzteqwBEADSirbLWsjgkQmdWr06jXPN8049MCqXQIZ2ovy9uJPyLkHgOCta
+8dmX+8Fkk5yNOLScjB1HUGJxAWJG+AhldW1xQGeo6loDfTW1mlfetq/zpW7CKbUp
+qve9eYYulneAy/81M/UoUZSzHqj6XY39wzJCH20H+Qx3WwcqXgSU7fSFXyJ4EBYs
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+G4vQ/QbzucK77Q==
+=eD3N
+-----END PGP PUBLIC KEY BLOCK-----
\ No newline at end of file
diff --git a/mongodb/files/server-4.4.gpg b/mongodb/files/server-4.4.gpg
new file mode 100644
index 00000000..f1b1730e
Binary files /dev/null and b/mongodb/files/server-4.4.gpg differ
diff --git a/mongodb/tasks/main.yml b/mongodb/tasks/main.yml
index a054a5fd..1d238b00 100644
--- a/mongodb/tasks/main.yml
+++ b/mongodb/tasks/main.yml
@@ -12,4 +12,7 @@
   when: ansible_distribution_release == "stretch"
 
 - include: main_buster.yml
-  when: ansible_distribution_major_version is version('10', '>=')
+  when: ansible_distribution_release == "buster"
+
+- include: main_bullseye.yml
+  when: ansible_distribution_major_version is version('11', '>=')
diff --git a/mongodb/tasks/main_bullseye.yml b/mongodb/tasks/main_bullseye.yml
new file mode 100644
index 00000000..63b2193b
--- /dev/null
+++ b/mongodb/tasks/main_bullseye.yml
@@ -0,0 +1,95 @@
+---
+
+# https://wiki.debian.org/DebianRepository/UseThirdParty
+- name: MongoDB embedded GPG key is absent
+  apt_key:
+    id: "B8612B5D"
+    keyring: /etc/apt/trusted.gpg
+    state: absent
+
+- name: Add MongoDB GPG key
+  copy:
+    src: server-4.4.asc
+    dest: /etc/apt/trusted.gpg.d/mongodb-server-4.4.asc
+    force: yes
+    mode: "0644"
+    owner: root
+    group: root
+
+- name: enable APT sources list
+  apt_repository:
+    repo: deb http://repo.mongodb.org/apt/debian buster/mongodb-org/4.4 main
+    state: present
+    filename: mongodb-org-4.4
+    update_cache: yes
+
+- name: Install packages
+  apt:
+    name: mongodb-org
+    update_cache: yes
+    state: present
+  register: _mongodb_install_package
+
+- name: MongoDB service in enabled and started
+  systemd:
+    name: mongod
+    enabled: yes
+    state: started
+  when: _mongodb_install_package.changed
+
+- name: install dependency for monitoring
+  apt:
+    name: python3-pymongo
+    state: present
+
+- name: Custom configuration
+  template:
+    src: mongodb_bullseye.conf.j2
+    dest: "/etc/mongod.conf"
+    force: "{{ mongodb_force_config | bool | ternary('yes', 'no') }}"
+  notify: restart mongod
+
+- name: Configure logrotate
+  template:
+    src: logrotate_bullseye.j2
+    dest: /etc/logrotate.d/mongodb
+    force: yes
+    backup: no
+
+- name: Munin plugins local directory exists
+  file:
+    dest: /usr/local/share/munin/plugins/
+    state: directory
+    mode: "0755"
+
+- name: Munin plugins are present
+  copy:
+    src: "munin/{{ item }}"
+    dest: '/usr/local/share/munin/plugins/{{ item }}'
+    force: yes
+  with_items:
+    - mongo_btree
+    - mongo_collections
+    - mongo_conn
+    - mongo_docs
+    - mongo_lock
+    - mongo_mem
+    - mongo_ops
+    - mongo_page_faults
+  notify: restart munin-node
+
+- name: Enable core Munin plugins
+  file:
+    src: '/usr/local/share/munin/plugins/{{ item }}'
+    dest: /etc/munin/plugins/{{ item }}
+    state: link
+  with_items:
+    - mongo_btree
+    - mongo_collections
+    - mongo_conn
+    - mongo_docs
+    - mongo_lock
+    - mongo_mem
+    - mongo_ops
+    - mongo_page_faults
+  notify: restart munin-node
diff --git a/mongodb/templates/logrotate_bullseye.j2 b/mongodb/templates/logrotate_bullseye.j2
new file mode 100644
index 00000000..8239e880
--- /dev/null
+++ b/mongodb/templates/logrotate_bullseye.j2
@@ -0,0 +1,15 @@
+# {{ ansible_managed }}
+
+/var/log/mongodb/mongod.log {
+    daily
+    missingok
+    rotate 365
+    dateext
+    compress
+    delaycompress
+    notifempty
+    sharedscripts
+    postrotate
+       pidof mongod | xargs kill -USR1
+    endscript
+}
diff --git a/mongodb/templates/mongodb_bullseye.conf.j2 b/mongodb/templates/mongodb_bullseye.conf.j2
new file mode 100644
index 00000000..b61479bd
--- /dev/null
+++ b/mongodb/templates/mongodb_bullseye.conf.j2
@@ -0,0 +1,39 @@
+# mongodb.conf - {{ ansible_managed }}
+
+# for documentation of all options, see:
+#   http://docs.mongodb.org/manual/reference/configuration-options/
+
+# Where and how to store data.
+storage:
+  dbPath: /var/lib/mongodb
+  journal:
+    enabled: true
+#  engine:
+#  mmapv1:
+#  wiredTiger:
+
+# where to write logging data.
+systemLog:
+  destination: file
+  logRotate: reopen
+  logAppend: true
+  path: /var/log/mongodb/mongodb.log
+
+# network interfaces
+net:
+  port: {{ mongodb_port }}
+  bindIp: {{ mongodb_bind }}
+
+#security:
+
+#operationProfiling:
+
+#replication:
+
+#sharding:
+
+## Enterprise-Only Options:
+
+#auditLog:
+
+#snmp:
diff --git a/mysql-oracle/tasks/users.yml b/mysql-oracle/tasks/users.yml
index da1ca05f..e5a7e3da 100644
--- a/mysql-oracle/tasks/users.yml
+++ b/mysql-oracle/tasks/users.yml
@@ -5,6 +5,16 @@
   apt:
     name: python-mysqldb
     state: present
+  when: ansible_distribution_major_version is version('10', '<=')
+  tags:
+    - mysql
+
+# dependency for mysql_user and mysql_db
+- name: python3-mysqldb is installed (Ansible dependency)
+  apt:
+    name: python3-mysqldb
+    state: present
+  when: ansible_distribution_major_version is version('10', '>')
   tags:
     - mysql
 
diff --git a/mysql-oracle/tasks/utils.yml b/mysql-oracle/tasks/utils.yml
index e7573afe..e0520cee 100644
--- a/mysql-oracle/tasks/utils.yml
+++ b/mysql-oracle/tasks/utils.yml
@@ -17,7 +17,7 @@
 
 # mytop
 
-- name: "mytop is installed (jessie)"
+- name: "mytop is installed (Debian 9)"
   apt:
     name: mytop
     state: present
@@ -32,7 +32,7 @@
 #     name: mysql-utilities
 #   when: ansible_distribution_major_version is version('9', '>=')
 
-- name: "mytop dependencies are installed (stretch)"
+- name: "mytop dependencies are installed (Buster)"
   apt:
     name:
       - libconfig-inifiles-perl
@@ -46,13 +46,21 @@
     - mysql
   when: ansible_distribution_release == "stretch"
 
-- name: "Install dependencies for mytop (Debian 10 or later)"
+- name: "Install dependencies for mytop (Debian 10)"
   apt:
     name:
       - mariadb-client-10.3
       - libconfig-inifiles-perl
       - libterm-readkey-perl
-  when: ansible_distribution_major_version is version('10', '>=')
+  when: ansible_distribution_release == "buster"
+
+- name: "Install dependencies for mytop (Debian 11 or later)"
+  apt:
+    name:
+      - mariadb-client-10.5
+      - libconfig-inifiles-perl
+      - libterm-readkey-perl
+  when: ansible_distribution_major_version is version('11', '>=')
 
 - include_role:
     name: evolix/remount-usr
diff --git a/mysql/tasks/users_jessie.yml b/mysql/tasks/users_jessie.yml
index 99dd2d04..3a56a63d 100644
--- a/mysql/tasks/users_jessie.yml
+++ b/mysql/tasks/users_jessie.yml
@@ -6,13 +6,22 @@
   when: mysql_variant == "mariadb"
 
 # dependency for mysql_user and mysql_db
-
 - name: python-mysqldb is installed (Ansible dependency)
   apt:
     name: python-mysqldb
     state: present
+  when: ansible_distribution_major_version is version('10', '<=')
   tags:
-  - mysql
+    - mysql
+
+# dependency for mysql_user and mysql_db
+- name: python3-mysqldb is installed (Ansible dependency)
+  apt:
+    name: python3-mysqldb
+    state: present
+  when: ansible_distribution_major_version is version('10', '>')
+  tags:
+    - mysql
 
 - name: create a password for mysqladmin
   command: "apg -n 1 -m 16 -M lcN"
diff --git a/mysql/tasks/users_stretch.yml b/mysql/tasks/users_stretch.yml
index 574399af..2b9bec6b 100644
--- a/mysql/tasks/users_stretch.yml
+++ b/mysql/tasks/users_stretch.yml
@@ -1,13 +1,22 @@
 ---
 
 # dependency for mysql_user and mysql_db
-
 - name: python-mysqldb is installed (Ansible dependency)
   apt:
     name: python-mysqldb
     state: present
+  when: ansible_distribution_major_version is version('10', '<=')
   tags:
-  - mysql
+    - mysql
+
+# dependency for mysql_user and mysql_db
+- name: python3-mysqldb is installed (Ansible dependency)
+  apt:
+    name: python3-mysqldb
+    state: present
+  when: ansible_distribution_major_version is version('10', '>')
+  tags:
+    - mysql
 
 - name: create a password for mysqladmin
   command: "apg -n 1 -m 16 -M lcN"
diff --git a/mysql/tasks/utils.yml b/mysql/tasks/utils.yml
index b4abf059..f1a9cb24 100644
--- a/mysql/tasks/utils.yml
+++ b/mysql/tasks/utils.yml
@@ -17,7 +17,7 @@
 
 # mytop
 
-- name: "Install mytop (jessie)"
+- name: "Install mytop (Debian 9)"
   apt:
     name: mytop
     state: present
@@ -27,7 +27,7 @@
     - mysql
   when: ansible_distribution_release == "jessie"
 
-- name: "Install dependencies for mytop (stretch)"
+- name: "Install dependencies for mytop (Debian 9)"
   apt:
     name:
       - mariadb-client-10.1
@@ -35,13 +35,21 @@
       - libterm-readkey-perl
   when: ansible_distribution_release == "stretch"
 
-- name: "Install dependencies for mytop (Debian 10 or later)"
+- name: "Install dependencies for mytop (Debian 10)"
   apt:
     name:
       - mariadb-client-10.3
       - libconfig-inifiles-perl
       - libterm-readkey-perl
-  when: ansible_distribution_major_version is version('10', '>=')
+  when: ansible_distribution_release == "buster"
+
+- name: "Install dependencies for mytop (Debian 11 or later)"
+  apt:
+    name:
+      - mariadb-client-10.5
+      - libconfig-inifiles-perl
+      - libterm-readkey-perl
+  when: ansible_distribution_major_version is version('11', '>=')
 
 - name: Read debian-sys-maint password
   shell: 'cat /etc/mysql/debian.cnf | grep -m1 "password = .*" | cut -d" " -f3'
diff --git a/packweb-apache/templates/phpmyadmin_apt_preferences.j2 b/packweb-apache/templates/phpmyadmin_apt_preferences.j2
index 02578c0d..3a2d2833 100644
--- a/packweb-apache/templates/phpmyadmin_apt_preferences.j2
+++ b/packweb-apache/templates/phpmyadmin_apt_preferences.j2
@@ -1,3 +1,3 @@
 Package: phpmyadmin php-twig
 Pin: release a=buster-backports
-Pin-Priority: 999
\ No newline at end of file
+Pin-Priority: 999
diff --git a/php/handlers/main.yml b/php/handlers/main.yml
index 1aade6c1..973c0069 100644
--- a/php/handlers/main.yml
+++ b/php/handlers/main.yml
@@ -14,3 +14,8 @@
   service:
     name: php7.3-fpm
     state: restarted
+
+- name: restart php7.4-fpm
+  service:
+    name: php7.4-fpm
+    state: restarted
diff --git a/php/tasks/main.yml b/php/tasks/main.yml
index e9687e67..5cf46bec 100644
--- a/php/tasks/main.yml
+++ b/php/tasks/main.yml
@@ -12,3 +12,6 @@
 
 - include: main_buster.yml
   when: ansible_distribution_release == "buster"
+
+- include: main_bullseye.yml
+  when: ansible_distribution_release == "bullseye"
diff --git a/php/tasks/main_bullseye.yml b/php/tasks/main_bullseye.yml
new file mode 100644
index 00000000..bdeffe56
--- /dev/null
+++ b/php/tasks/main_bullseye.yml
@@ -0,0 +1,96 @@
+---
+
+- name: "Set variables (Debian 10 or later)"
+  set_fact:
+    php_cli_defaults_ini_file: /etc/php/7.4/cli/conf.d/z-evolinux-defaults.ini
+    php_cli_custom_ini_file: /etc/php/7.4/cli/conf.d/zzz-evolinux-custom.ini
+    php_apache_defaults_ini_file: /etc/php/7.4/apache2/conf.d/z-evolinux-defaults.ini
+    php_apache_custom_ini_file: /etc/php/7.4/apache2/conf.d/zzz-evolinux-custom.ini
+    php_fpm_defaults_ini_file: /etc/php/7.4/fpm/conf.d/z-evolinux-defaults.ini
+    php_fpm_custom_ini_file: /etc/php/7.4/fpm/conf.d/zzz-evolinux-custom.ini
+    php_fpm_debian_default_pool_file: /etc/php/7.4/fpm/pool.d/www.conf
+    php_fpm_default_pool_file: /etc/php/7.4/fpm/pool.d/www-evolinux-defaults.conf
+    php_fpm_default_pool_custom_file: /etc/php/7.4/fpm/pool.d/www-evolinux-zcustom.conf
+    php_fpm_default_pool_socket: /var/run/php/php7.4-fpm.sock
+    php_fpm_service_name: php7.4-fpm
+
+# Packages
+
+- name: "Set package list (Debian 9 or later)"
+  set_fact:
+    php_stretch_packages:
+      - php-cli
+      - php-gd
+      - php-intl
+      - php-imap
+      - php-ldap
+      - php-mysql
+      # php-mcrypt is no longer packaged for PHP 7.2
+      - php-pgsql
+      - php-sqlite3
+      - php-curl
+      - php-ssh2
+      - php-zip
+      - composer
+      - libphp-phpmailer
+
+- include: sury_pre.yml
+  when: php_sury_enable
+
+- name: "Install PHP packages (Debian 9 or later)"
+  apt:
+    name: '{{ php_stretch_packages }}'
+    state: present
+
+- name: "Install mod_php packages (Debian 9 or later)"
+  apt:
+    name:
+      - libapache2-mod-php
+      - php
+    state: present
+  when: php_apache_enable
+
+- name: "Install PHP FPM packages (Debian 9 or later)"
+  apt:
+    name:
+      - php-fpm
+      - php
+    state: present
+  when: php_fpm_enable
+
+# Configuration
+
+- name: Enforce permissions on PHP directory
+  file:
+    dest: "{{ item }}"
+    mode: "0755"
+  with_items:
+    - /etc/php
+    - /etc/php/7.4
+
+- include: config_cli.yml
+- name: Enforce permissions on PHP cli directory
+  file:
+    dest: /etc/php/7.4/cli
+    mode: "0755"
+
+- include: config_fpm.yml
+  when: php_fpm_enable
+
+- name: Enforce permissions on PHP fpm directory
+  file:
+    dest: /etc/php/7.4/fpm
+    mode: "0755"
+  when: php_fpm_enable
+
+- include: config_apache.yml
+  when: php_apache_enable
+
+- name: Enforce permissions on PHP apache2 directory
+  file:
+    dest: /etc/php/7.4/apache2
+    mode: "0755"
+  when: php_apache_enable
+
+- include: sury_post.yml
+  when: php_sury_enable
diff --git a/postgresql/tasks/main.yml b/postgresql/tasks/main.yml
index fbe22989..1783a763 100644
--- a/postgresql/tasks/main.yml
+++ b/postgresql/tasks/main.yml
@@ -5,10 +5,10 @@
   when: ansible_distribution_release == "jessie"
 
 - include: packages_stretch.yml
-  when: ansible_distribution_major_version is version('9', '=')
+  when: ansible_distribution_release == "stretch"
 
 - include: packages_buster.yml
-  when: ansible_distribution_major_version is version('10', '=')
+  when: ansible_distribution_release == "buster"
 
 - include: packages_bullseye.yml
   when: ansible_distribution_major_version is version('11', '>=')
diff --git a/postgresql/tasks/nrpe.yml b/postgresql/tasks/nrpe.yml
index 740c7b08..9c22e293 100644
--- a/postgresql/tasks/nrpe.yml
+++ b/postgresql/tasks/nrpe.yml
@@ -9,10 +9,17 @@
   register: postgresql_nrpe_password
   changed_when: False
 
-- name: Install python dependencies for postgresql_user
+- name: python-psycopg2 is installed (Ansible dependency)
   apt:
     name: python-psycopg2
     state: present
+  when: ansible_distribution_major_version is version('10', '<=')
+
+- name: python3-psycopg2 is installed (Ansible dependency)
+  apt:
+    name: python3-psycopg2
+    state: present
+  when: ansible_distribution_major_version is version('10', '>')
 
 - name: Is nrpe present ?
   stat:
diff --git a/rabbitmq/tasks/nrpe.yml b/rabbitmq/tasks/nrpe.yml
index c4c700df..75b37043 100644
--- a/rabbitmq/tasks/nrpe.yml
+++ b/rabbitmq/tasks/nrpe.yml
@@ -1,9 +1,16 @@
 ---
 
-- name: check_rabbitmq dependencies
+- name: python-requests is installed (check_rabbitmq dependency)
   apt:
     name: python-requests
     state: present
+  when: ansible_distribution_major_version is version('10', '<=')
+
+- name: python3-requests is installed (check_rabbitmq dependency)
+  apt:
+    name: python3-requests
+    state: present
+  when: ansible_distribution_major_version is version('10', '>')
 
 - include_role:
     name: evolix/remount-usr
diff --git a/redis/templates/redis-server@bullseye.service.j2 b/redis/templates/redis-server@bullseye.service.j2
new file mode 100644
index 00000000..623eb919
--- /dev/null
+++ b/redis/templates/redis-server@bullseye.service.j2
@@ -0,0 +1,45 @@
+[Unit]
+Description=Advanced key-value store
+After=network.target
+Documentation=http://redis.io/documentation, man:redis-server(1)
+
+[Service]
+Type=notify
+ExecStart=/usr/bin/redis-server {{ redis_conf_dir_prefix }}-%i/redis.conf --supervised systemd --daemonize no
+PIDFile=/run/redis-%i/redis-server.pid
+TimeoutStopSec=0
+Restart=always
+User=redis-%i
+Group=redis-%i
+RuntimeDirectory=redis-%i
+RuntimeDirectoryMode=2755
+
+UMask=007
+PrivateTmp=yes
+LimitNOFILE=65535
+PrivateDevices=yes
+ProtectHome={{ redis_data_dir_prefix is match('/home') | ternary('no', 'yes') }}
+ReadOnlyDirectories=/
+ReadWritePaths=-{{ redis_data_dir_prefix }}-%i
+ReadWritePaths=-{{ redis_log_dir_prefix }}-%i
+ReadWritePaths=-{{ redis_pid_dir_prefix }}-%i
+ReadWritePaths=-{{ redis_socket_dir_prefix }}-%i
+
+NoNewPrivileges=true
+CapabilityBoundingSet=CAP_SETGID CAP_SETUID CAP_SYS_RESOURCE
+MemoryDenyWriteExecute=true
+ProtectKernelModules=true
+ProtectKernelTunables=true
+ProtectControlGroups=true
+RestrictRealtime=true
+RestrictNamespaces=true
+RestrictAddressFamilies=AF_INET AF_INET6 AF_UNIX
+
+# redis-server can write to its own config file when in cluster mode so we
+# permit writing there by default. If you are not using this feature, it is
+# recommended that you replace the following lines with "ProtectSystem=full".
+ProtectSystem=true
+ReadWriteDirectories=-{{ redis_conf_dir_prefix }}-%i
+
+[Install]
+WantedBy=multi-user.target
\ No newline at end of file
diff --git a/redmine/tasks/packages.yml b/redmine/tasks/packages.yml
index b2be8faa..0c65df44 100644
--- a/redmine/tasks/packages.yml
+++ b/redmine/tasks/packages.yml
@@ -1,5 +1,5 @@
 ---
-- name: Install dependancy
+- name: Install dependency
   apt:
     name:
       - libpam-systemd
@@ -14,7 +14,24 @@
       - libmagickwand-dev
       - libmagickcore-dev
       - libmariadbclient-dev
-      - python-mysqldb
     state: present
   tags:
     - redmine
+
+# dependency for mysql_user and mysql_db
+- name: python-mysqldb is installed (Ansible dependency)
+  apt:
+    name: python-mysqldb
+    state: present
+  when: ansible_distribution_major_version is version('10', '<=')
+  tags:
+    - redmine
+
+# dependency for mysql_user and mysql_db
+- name: python3-mysqldb is installed (Ansible dependency)
+  apt:
+    name: python3-mysqldb
+    state: present
+  when: ansible_distribution_major_version is version('10', '>')
+  tags:
+    - redmine
\ No newline at end of file
diff --git a/squid/files/systemd-override.conf b/squid/files/systemd-override.conf
deleted file mode 100644
index eab76a17..00000000
--- a/squid/files/systemd-override.conf
+++ /dev/null
@@ -1,4 +0,0 @@
-# systemd override for Squid
-[Service]
-ExecStart=
-ExecStart=/usr/sbin/squid -sYC -f /etc/squid/evolinux-defaults.conf
diff --git a/squid/tasks/main.yml b/squid/tasks/main.yml
index 9e00dcb0..4a3cab4d 100644
--- a/squid/tasks/main.yml
+++ b/squid/tasks/main.yml
@@ -22,6 +22,13 @@
       - squidclient
     state: present
 
+- name: Fetch packages
+  package_facts:
+    manager: auto  
+
+- debug:
+    var: ansible_facts.packages[squid_daemon_name]
+
 - name: "Set alternative config file (Debian 9 or later)"
   copy:
     src: default_squid
diff --git a/squid/tasks/systemd.yml b/squid/tasks/systemd.yml
index 82b8760c..ac9eb7e9 100644
--- a/squid/tasks/systemd.yml
+++ b/squid/tasks/systemd.yml
@@ -16,8 +16,8 @@
     mode: "0755"
 
 - name: "Squid systemd unit service is present"
-  copy:
-    src: systemd-override.conf
+  template:
+    src: systemd-override.conf.j2
     dest: /etc/systemd/system/squid.service.d/override.conf
     force: yes
   register: _squid_systemd_override
diff --git a/squid/templates/evolinux-custom.conf.j2 b/squid/templates/evolinux-custom.conf.j2
index cc465dc7..27c97cc2 100644
--- a/squid/templates/evolinux-custom.conf.j2
+++ b/squid/templates/evolinux-custom.conf.j2
@@ -1,4 +1,4 @@
 http_port 8888 transparent
 cache deny all
-ignore_expect_100 on
+{% if ansible_facts.packages[squid_daemon_name][0]['version'] is version (4, '<') %}ignore_expect_100 on{% endif %}
 tcp_outgoing_address {{ squid_address }}
diff --git a/squid/templates/systemd-override.conf.j2 b/squid/templates/systemd-override.conf.j2
new file mode 100644
index 00000000..ee3ff666
--- /dev/null
+++ b/squid/templates/systemd-override.conf.j2
@@ -0,0 +1,8 @@
+# systemd override for Squid
+[Service]
+ExecStart=
+{% if ansible_distribution_major_version is version('11', '>=') %}
+ExecStart=/usr/sbin/squid --foreground -sYC -f /etc/squid/evolinux-defaults.conf
+{% else %}
+ExecStart=/usr/sbin/squid -sYC -f /etc/squid/evolinux-defaults.conf
+{% endif %}
diff --git a/tomcat/tasks/packages.yml b/tomcat/tasks/packages.yml
index 900dffd0..9b7995cc 100644
--- a/tomcat/tasks/packages.yml
+++ b/tomcat/tasks/packages.yml
@@ -21,6 +21,13 @@
     - ansible_distribution_release == "buster"
     - tomcat_version is not defined
 
+- name: Set Tomcat version to 10 on Debian 11 if missing
+  set_fact:
+    tomcat_version: 10
+  when:
+    - ansible_distribution_release == "bullseye"
+    - tomcat_version is not defined
+
 - name: Install packages
   apt:
     name:
diff --git a/varnish/tasks/main.yml b/varnish/tasks/main.yml
index 95a720c8..75268841 100644
--- a/varnish/tasks/main.yml
+++ b/varnish/tasks/main.yml
@@ -52,6 +52,7 @@
     - config
     - update-config
 
+# TODO: verify if it's still necessary for Debian 11
 - name: Override Varnish systemd unit (Buster and later)
   template:
     src: varnish.conf.buster.j2
diff --git a/webapps/nextcloud/tasks/main.yml b/webapps/nextcloud/tasks/main.yml
index 2c525114..c63291f1 100644
--- a/webapps/nextcloud/tasks/main.yml
+++ b/webapps/nextcloud/tasks/main.yml
@@ -16,7 +16,24 @@
     - php-apcu
     - php-redis
     - php-bcmath
-    - python-mysqldb
+  tags:
+    - nextcloud
+
+# dependency for mysql_user and mysql_db
+- name: python-mysqldb is installed (Ansible dependency)
+  apt:
+    name: python-mysqldb
+    state: present
+  when: ansible_distribution_major_version is version('10', '<=')
+  tags:
+    - nextcloud
+
+# dependency for mysql_user and mysql_db
+- name: python3-mysqldb is installed (Ansible dependency)
+  apt:
+    name: python3-mysqldb
+    state: present
+  when: ansible_distribution_major_version is version('10', '>')
   tags:
     - nextcloud