The dnsutl package is a collection tools to make administering DNS easier. These include reverse map generation, validation, and much more. All of these programs are robust when faced with all the peculiar semantics of DNS resource files.
IP change detection script for UNIX systems. Can be used to map static domain to dynamic IP. Works behind NAT. Uses HTTP browser or network interface to get public IP. To be used with task scheduler (Cron or like, sample crontab file shipped).