diff --git a/group_vars/all/main.yml b/group_vars/all/main.yml
index 70f2104..2ebf17d 100644
--- a/group_vars/all/main.yml
+++ b/group_vars/all/main.yml
@@ -112,6 +112,7 @@ copy_plain_files_sysctl:
     src_path: etc/sysctl.d/10-ddos.conf
     dest_path: /etc/sysctl.d/10-ddos.conf
 
+copy_additional_plain_files_sysctl: []
 
 
 # ---
@@ -1053,7 +1054,7 @@ sshd_authorized_keys_file: ".ssh/authorized_keys .ssh/authorized_keys2"
 
 sshd_pubkey_authentication: !!str "yes"
 
-sshd_password_authentication: !!str "yes"
+sshd_password_authentication: !!str "no"
 
 sshd_use_pam: !!str "yes"
 
@@ -1093,6 +1094,7 @@ sshd_hostkeyalgorithms:
 #      - chacha20-poly1305@openssh.com
 #      - aes256-gcm@openssh.com
 #      - aes256-ctr
+
 #sshd_ciphers: {}
 sshd_ciphers:
   - chacha20-poly1305@openssh.com
diff --git a/hosts b/hosts
index 2c34601..c488014 100644
--- a/hosts
+++ b/hosts
@@ -18,7 +18,6 @@ dns1.warenform.de
 
 [extra_hosts]
 backup.oopen.de
-backup-neu.oopen.de
 
 gitea.so36.net
 backup.so36.net
@@ -150,15 +149,17 @@ o24.oopen.de
 cl-irights.oopen.de
 mm-irights.oopen.de
 
-# - o25.oopen.de
-o25.oopen.de
+# - o27.oopen.de
+o27.oopen.de
 cl-fm.oopen.de
+cl-fm-neu.oopen.de
 mail.faire-mobilitaet.de
+mail-neu.faire-mobilitaet.de
 
 # Hetzner Cloud CX31 - AK
 o26.oopen.de
 
-# Backup Server
+# Backup Faire Mobilitaet
 o28.oopen.de
 
 # Backup Server
@@ -196,9 +197,6 @@ web-03.oopen.de
 web-test.oopen.de
 cl-test.oopen.de
 
-# Backup Faire Mobilitaet
-o37.oopen.de
-
 lxc-host-kb.anw-kb.netz
 
 
@@ -349,26 +347,26 @@ o24.oopen.de
 cl-irights.oopen.de
 mm-irights.oopen.de
 
-# - o25.oopen.de
-o25.oopen.de
+# - o27.oopen.de
+o27.oopen.de
 cl-fm.oopen.de
+cl-fm-neu.oopen.de
 mail.faire-mobilitaet.de
+mail-neu.faire-mobilitaet.de
 
 # Hetzner Cloud CX31 - AK
 o26.oopen.de
 
-# - o28.oopen.de
+# Backup Faire Mobilitaet
 o28.oopen.de
+
+# - o29.oopen.de
+o29.oopen.de
 backup.oopen.de
 git.oopen.de
 munin.oopen.de
 nscache.oopen.de
 
-# - o29.oopen.de
-o29.oopen.de
-backup-neu.oopen.de
-git-neu.oopen.de
-
 # AK - Server Nextcloud/Jitsi Meet
 o30.oopen.de
 meet.akweb.de
@@ -402,9 +400,6 @@ web-03.oopen.de
 web-test.oopen.de
 cl-test.oopen.de
 
-# Backup Faire Mobilitaet
-o37.oopen.de
-
 lxc-host-kb.anw-kb.netz
 
 # ---
@@ -487,10 +482,9 @@ o13-web.oopen.de
 test.mariadb.oopen.de
 test.mx.oopen.de
 
-# o28.oopen.de
-munin.oopen.de
-
 # o29.oopen.de
+backup.oopen.de
+munin.oopen.de
 
 # o20.oopen.de (srv-cityslang.cityslang.com)
 o20.oopen.de
@@ -510,9 +504,17 @@ cl-01.oopen.de
 # o24.oopen.de
 cl-irights.oopen.de
 
-# o25.oopen.de
+# o27.oopen.de
 cl-fm.oopen.de
+cl-fm-neu.oopen.de
 mail.faire-mobilitaet.de
+mail-neu.faire-mobilitaet.de
+
+# Backup Faire Mobilitaet
+o28.oopen.de
+
+# o29.oopen.de
+backup.oopen.de
 
 # o30.oopen.de - AK server Jitsi Meet/Nextcloud
 cloud.akweb.de
@@ -532,9 +534,6 @@ web-test.oopen.de
 b.mx.oopen.de
 cl-test.oopen.de
 
-# Backup Faire Mobilitaet
-o37.oopen.de
-
 # ---
 #  O.OPEN office network
 # ---
@@ -744,8 +743,9 @@ test.mx.oopen.de
 # o21.oopen.de
 mail.cadus.org
 
-# o25.oopen.de
+# o27.oopen.de
 mail.faire-mobilitaet.de
+mail-neu.faire-mobilitaet.de
 
 # o35.oopen.de
 e.mx.oopen.de
@@ -788,8 +788,9 @@ lists.mx.warenform.de
 o13-board.oopen.de
 o13-mail.oopen.de
 
-# o25.oopen.de
+# o27.oopen.de
 mail.faire-mobilitaet.de
+mail-neu.faire-mobilitaet.de
 
 # o35.oopen.de
 e.mx.oopen.de
@@ -863,12 +864,19 @@ moodle.oopen.de
 cl-irights.oopen.de
 mm-irights.oopen.de
 
-# o25.oopen.de
-cl-fm.oopen.de
-
 # Hetzner Cloud CX31 - AK
 o26.oopen.de
 
+# o27.oopen.de
+cl-fm.oopen.de
+cl-fm-neu.oopen.de
+
+# Backup Faire Mobilitaet
+o28.oopen.de
+
+# o29.oopen.de
+backup.oopen.de
+
 # o30.oopen.de - AK server Jitsi Meet/Nextcloud
 cloud.akweb.de
 
@@ -888,9 +896,6 @@ web-03.oopen.de
 web-test.oopen.de
 cl-test.oopen.de
 
-# Backup Faire Mobilitaet
-o37.oopen.de
-
 
 # ---
 # Warenform
@@ -947,9 +952,15 @@ cl-01.oopen.de
 # o24.oopen.de
 cl-irights.oopen.de
 
-# o25.oopen.de
+# o27.oopen.de
 cl-fm.oopen.de
 
+# o28.oopen.de
+o28.oopen.de
+
+# o29.oopen.de
+backup.oopen.de
+
 # o30.oopen.de - AK server Jitsi Meet/Nextcloud
 cloud.akweb.de
 
@@ -997,7 +1008,7 @@ o13-mail.oopen.de
 # o17.oopen.de
 test.mx.oopen.de
 
-# o28.oopen.de
+# o29.oopen.de
 nscache.oopen.de
 
 # o21.oopen.de
@@ -1005,8 +1016,9 @@ mail.cadus.org
 
 o22.oopen.de
 
-# o25.oopen.de
+# o27.oopen.de
 mail.faire-mobilitaet.de
+mail-neu.faire-mobilitaet.de
 
 # o35.oopen.de
 d.mx.oopen.de
@@ -1069,7 +1081,7 @@ backup-neu.oopen.de
 devel-root.wf.netz
 
 # Backup Faire Mobilitaet
-o37.oopen.de
+o28.oopen.de
 
 # ---
 # Warenform
@@ -1155,8 +1167,7 @@ o21.oopen.de
 o22.oopen.de
 o23.oopen.de
 o24.oopen.de
-o25.oopen.de
-o28.oopen.de
+o27.oopen.de
 o29.oopen.de
 o30.oopen.de
 o32.oopen.de
@@ -1248,23 +1259,20 @@ moodle.oopen.de
 cl-irights.oopen.de
 mm-irights.oopen.de
 
-# - o25.oopen.de
+# - o27.oopen.de
 cl-fm.oopen.de
+cl-fm-neu.oopen.de
 mail.faire-mobilitaet.de
+mail-neu.faire-mobilitaet.de
 
 # Hetzner Cloud CX31 - AK
 o26.oopen.de
 
-# o28.oopen.de
+# o29.oopen.de
 backup.oopen.de
 git.oopen.de
-nscache.oopen.de
 munin.oopen.de
-nc-gw.oopen.de
-
-# o29.oopen.de
-backup-neu.oopen.de
-git-neu.oopen.de
+nscache.oopen.de
 
 # o30.oopen.de - AK Server Nextcloud/Jitsi Meet
 meet.akweb.de
@@ -1433,26 +1441,25 @@ o24.oopen.de
 cl-irights.oopen.de
 mm-irights.oopen.de
 
-# - o25.oopen.de
-o25.oopen.de
+# - o27.oopen.de
+o27.oopen.de
 cl-fm.oopen.de
+cl-fm-neu.oopen.de
 mail.faire-mobilitaet.de
+mail-neu.faire-mobilitaet.de
 
 # Hetzner Cloud CX31 - AK
 o26.oopen.de
 
-# - o28.oopen.de
+# Backup Faire Mobilitaet
 o28.oopen.de
+
+# - o29.oopen.de
+o29.oopen.de
 backup.oopen.de
 git.oopen.de
 nscache.oopen.de
 munin.oopen.de
-nc-gw.oopen.de
-
-# - o29.oopen.de
-o29.oopen.de
-backup-neu.oopen.de
-git-neu.oopen.de
 
 # AK - Server Nextcloud/Jitsi Meet
 o30.oopen.de
@@ -1486,9 +1493,6 @@ web-01.oopen.de
 web-test.oopen.de
 cl-test.oopen.de
 
-# Backup Faire Mobilitaet
-o37.oopen.de
-
 lxc-host-kb.anw-kb.netz
 
 
diff --git a/roles/common/files/etc/sysctl.d/30-enable-ipv6.conf b/roles/common/files/etc/sysctl.d/30-enable-ipv6.conf
new file mode 100644
index 0000000..7ad2c64
--- /dev/null
+++ b/roles/common/files/etc/sysctl.d/30-enable-ipv6.conf
@@ -0,0 +1,4 @@
+
+# Enable packet forwarding for IPv6
+#
+net.ipv6.conf.all.forwarding = 1
diff --git a/roles/common/files/etc/sysctl.d/60-elasticsearch.conf b/roles/common/files/etc/sysctl.d/60-elasticsearch.conf
new file mode 100644
index 0000000..7c197d5
--- /dev/null
+++ b/roles/common/files/etc/sysctl.d/60-elasticsearch.conf
@@ -0,0 +1,8 @@
+
+# Needed by ElasticSearch Installation on virtual guest
+# systems (LX-Containers)
+#
+# The error message there was:
+#    max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]
+#
+vm.max_map_count = 524288
diff --git a/roles/common/handlers/main.yml b/roles/common/handlers/main.yml
index dd7404d..fec35b3 100644
--- a/roles/common/handlers/main.yml
+++ b/roles/common/handlers/main.yml
@@ -54,6 +54,11 @@
     name: systemd-journald
     state: restarted
 
+- name: Restart redis-server
+  service:
+    name: redis-server
+    state: restarted
+
 - name: Restart tor service
   service: 
     name: tor
diff --git a/roles/common/tasks/basic.yml b/roles/common/tasks/basic.yml
index 8adc901..1154441 100644
--- a/roles/common/tasks/basic.yml
+++ b/roles/common/tasks/basic.yml
@@ -126,6 +126,23 @@
   tags:
     - systctl-config
 
+- name: (basic.yml) Additional Kernel Parameters (files  /etc/sysctl.d/*.conf)
+  copy:
+    src: '{{ item.src_path }}'
+    dest: '{{ item.dest_path }}'
+    owner: root
+    group: root
+    mode: '0644'
+  loop: "{{ copy_additional_plain_files_sysctl }}"
+  loop_control:
+    label: 'dest: {{ item.name }}'
+  when: 
+    - inventory_hostname not in groups['lxc_guest']
+    - copy_additional_plain_files_sysctl is defined
+    - copy_additional_plain_files_sysctl|length > 0
+  tags:
+    - systctl-config
+
 
 # ----------
 # unattended upgrades
diff --git a/roles/common/tasks/main.yml b/roles/common/tasks/main.yml
index b5c1e2c..9b896de 100644
--- a/roles/common/tasks/main.yml
+++ b/roles/common/tasks/main.yml
@@ -188,6 +188,14 @@
   tags:
     - samba-server
 
+- import_tasks: redis-server.yml
+  when: inventory_hostname in groups['nextcloud_server'] or 
+        inventory_hostname in groups['apache2_webserver'] or
+        inventory_hostname in groups['nginx_webserver']
+  tags:
+    - redis-server
+   
+
 # tags supportetd inside caching-nameserver.yml
 #
 # apt-caching-nameserver
diff --git a/roles/common/tasks/redis-server.yml b/roles/common/tasks/redis-server.yml
new file mode 100644
index 0000000..7f77929
--- /dev/null
+++ b/roles/common/tasks/redis-server.yml
@@ -0,0 +1,111 @@
+
+---
+
+- name: (redis-server.yml) update
+  apt:
+    update_cache: true
+    cache_valid_time: "{{ 0 if apt_config_updated is defined and apt_config_updated.changed else apt_update_cache_valid_time }}"
+  when: apt_update|bool
+  tags:
+    - redis-server
+
+
+- name: (redis-server.yml) dpkg --configure
+  command: >
+    dpkg --configure -a
+  args:
+    warn: false
+  changed_when: _dpkg_configure.stdout_lines | length
+  register: _dpkg_configure
+  when: apt_dpkg_configure|bool
+  tags:
+    - redis-server
+
+
+- name: (redis-server.yml) upgrade
+  apt:
+    upgrade: "{{ apt_upgrade_type }}"
+    update_cache: true
+    dpkg_options: "{{ apt_upgrade_dpkg_options | join(',') }}"
+  when: apt_upgrade|bool
+  tags:
+    - redis-server
+
+
+- name: (redis-server.yml) Install redis-server packages
+  apt:
+    name: redis-server
+    state: present
+  tags:
+    - redis-server
+
+- name: (redis-server.yml) Determine available users
+  getent:
+    database: passwd
+  tags:
+    - redis-server
+
+- name: (redis-server.yml) Determine available groups
+  getent:
+    database: group
+  tags:
+    - redis-server
+
+- name: (redis-server.yml) Add user 'www-data' to group 'redis'
+  user:
+    name: www-data
+    groups: redis
+    append: yes
+  when:
+    - "'www-data' in my_users"
+    - "'redis' in my_groups"
+  vars:
+     my_users: "{{ getent_passwd.keys()|list }}"
+     my_groups: "{{ getent_group.keys()|list }}"
+  tags:
+    - redis-server
+
+- name: (redis-server.yml) Add user 'webadmin' to group 'redis'
+  user:
+    name: webadmin
+    groups: redis
+    append: yes
+  when:
+    - "'webadmin' in my_users"
+    - "'redis' in my_groups"
+  vars:
+     my_users: "{{ getent_passwd.keys()|list }}"
+     my_groups: "{{ getent_group.keys()|list }}"
+  tags:
+    - redis-server
+
+- name: (redis-server.yml)  Check if file '/etc/redis/redis.conf.ORIG' exists
+  stat:
+    path: /etc/redis/redis.conf.ORIG
+  register: redis_conf_exists
+  tags:
+    - redis-server
+
+- name: (redis-server.yml) Backup existing file /etc/redis/redis.conf.
+  command: cp -a /etc/redis/redis.conf /etc/redis/redis.conf.ORIG
+  when:
+    - redis_conf_exists.stat.exists == False
+  tags:
+    - samba-server
+
+- name: (redis-server.yml) adjust configuration '/etc/redis/redis.conf'
+  lineinfile:
+    dest: /etc/redis/redis.conf
+    regexp: "{{ item.regexp }}"
+    insertafter: "{{ item.insertafter }}"
+    line: "{{ item.key }} {{ item.val }}"
+    state: present
+  loop:
+      - { regexp: '^bind\s+', key: 'bind', val: '127.0.0.1 ::1', insertafter: '^#\s*bind\s+' }
+      - { regexp: '^port\s+', key: 'port', val: '6379', insertafter: '^#\s*port\s+' }
+      - { regexp: '^unixsocket\s+', key: 'unixsocket', val: '/run/redis/redis-server.sock', insertafter: '^#\s*unixsocketperm' }
+      - { regexp: '^unixsocketperm', key: 'unixsocketperm', val: '770', insertafter: '^unixsocket\s+' }
+      - { regexp: '^logfile', key: 'logfile',  val: '/var/log/redis/redis-server.log', insertafter: '^#\s+logfile\s+' }
+  notify: "Restart redis-server"
+  tags:
+    - redis-server