$TTL    3600
@       IN      SOA     sethi.mos.  root.mos. (
                   2007010401           ; Serial
                         3600           ; Refresh [1h]
                          600           ; Retry   [10m]
                        86400           ; Expire  [1d]
                          600 )         ; Negative Cache TTL [1h]
;
@       IN      NS      sethi.mos.

10.0.80.80.in-addr.arpa       IN      PTR    kheops.mos.
20.0.80.80.in-addr.arpa       IN      PTR    sethi.mos.
1.0.80.80.in-addr.arpa       IN      PTR     host1.mos.
2.0.80.80.in-addr.arpa      IN      PTR    host2.mos.
3.0.80.80.in-addr.arpa       IN      PTR     host3.mos.
4.0.80.80.in-addr.arpa       IN      PTR     host4.mos.
5.0.80.80.in-addr.arpa       IN      PTR    host5.mos.