diff --git a/roles/prerequisites/README.md b/roles/prerequisites/README.md
index f1120c9..5cd087a 100644
--- a/roles/prerequisites/README.md
+++ b/roles/prerequisites/README.md
@@ -2,18 +2,17 @@
 
 Diese Ansible role prüft ob die Voraussetzungen für ein Freifunk Gateway erfüllt sind.
 
-- Forward-DNS Eintrag == ausgelesener IPv4-Adresse
-- Forward-DNS Eintrag == ausgelesener IPv6-Adresse
+- Forward-DNS Eintrag $FQDN == ausgelesener IPv4-Adresse
+- Forward-DNS Eintrag $FQDN == ausgelesener IPv6-Adresse
+- CNAME Eintrag gate$magic.freifunk-mwu.de == $FQDN
+- CNAME Eintrag icvpn$magic.freifunk-mwu.de == $FQDN
 - Linux Distribution == Debian
 - Debian Version == 9
 
 ## Benötigte Variablen
 
+Die folgenden Variablen werden über einen DNS Lookup gesetzt:
 - Variable `dns_host_ipv4_address` (Rollen-Variable)
-```
-dns_host_ipv4_address: "{{ lookup('dig', inventory_hostname, 'qtype=A') }}"
-```
 - Variable `dns_host_ipv6_address` (Rollen-Variable)
-```
-dns_host_ipv6_address: "{{ lookup('dig', inventory_hostname, 'qtype=AAAA') }}"
-```
+- Variable `dns_gate_num_cname` (Rollen-Variable)
+- Variable `dns_gate_icvpn_cname` (Rollen-Variable)
diff --git a/roles/prerequisites/tasks/main.yml b/roles/prerequisites/tasks/main.yml
index b5f19bc..43f2cb9 100755
--- a/roles/prerequisites/tasks/main.yml
+++ b/roles/prerequisites/tasks/main.yml
@@ -5,6 +5,8 @@
     that:
       - "dns_host_ipv4_address in ansible_all_ipv4_addresses"
       - "dns_host_ipv6_address in ansible_all_ipv6_addresses"
+      - "dns_gate_num_cname == inventory_hostname"
+      - "dns_gate_icvpn_cname == inventory_hostname"
       - "ansible_distribution == 'Debian'"
       - "ansible_distribution_major_version == '9'"
 
diff --git a/roles/prerequisites/vars/main.yml b/roles/prerequisites/vars/main.yml
index f0e8dca..6cb0cdd 100644
--- a/roles/prerequisites/vars/main.yml
+++ b/roles/prerequisites/vars/main.yml
@@ -1,4 +1,8 @@
 ---
+dns_gate_num: "gate{{ magic }}.{{ http_domain_external }}"
+dns_gate_icvpn: "icvpn{{ magic }}.{{ http_domain_external }}"
 
 dns_host_ipv4_address: "{{ lookup('dig', inventory_hostname, 'qtype=A') }}"
 dns_host_ipv6_address: "{{ lookup('dig', inventory_hostname, 'qtype=AAAA') }}"
+dns_gate_num_cname: "{{ lookup('dig', dns_gate_num, 'qtype=CNAME') | regex_replace('\\.$') }}"
+dns_gate_icvpn_cname: "{{ lookup('dig', dns_gate_icvpn, 'qtype=CNAME') | regex_replace('\\.$') }}"