If you are running BIND 9, you have handy new tools to help maintain your nameserver files: named-checkconf and named-checkzone. These tools reside in /usr/sbin or /usr/local/sbin.
named-checkconf checks the configuration file for syntax errors.
$ /usr/sbin/named-checkconf zonename db.local
zone zonename/IN: loaded serial 1
OK
named-checkzone checks a zone file for syntax errors.
$ /usr/sbin/named-checkzone zonename pri.108.10.20.in-addr.arpa
zone zonename/IN: loaded serial 2004071902
OK
