$TTL 86400 @ IN SOA etcdns.local. root.etcdns.local. ( 100500 ; Serial 604800 ; Refresh 86400 ; Retry 2419200 ; Expire 86400 ) ; Negative Cache TTL IN NS ns.etcdns.local. IN A 127.0.0.1 1 IN PTR m1.etcd.local. 1 IN PTR m2.etcd.local. 1 IN PTR m3.etcd.local. 1 IN PTR m4.etcd.local. 1 IN PTR m5.etcd.local. 1 IN PTR m6.etcd.local.