/var/named/cluster.zone

$TTL 86400 ; 1 day @ IN SOA cluster. root.bert.cluster. ( 51 ; serial 8h ; refresh (8 hours) 2h ; retry (2 hours) 1w ; expire (1 week) 86400 ; minimum (1 day) ) cluster. IN NS bert.cluster. bert.cluster. IN A 172.12.0.1 bert.chem.gac.edu. IN CNAME bert.cluster. gus.cluster. IN A 172.12.0.2