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+# Ansible role prerequisites
+
+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
+- Linux Distribution == Debian
+- Debian Version == 9
+
+## Benötigte Variablen
+
+- 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') }}"
+```