Depends on what type of dns server it is...
in both cases, you do a backup of system state and it will save these settings too.
if not an AD integrated zone, you can backup your zone files as they are just text files, this will not save all the dns server settings though. If AD integrated, the data is saved with a system state backup as it is part of AD.
system state is the only way to backup server data
Aftertaf
"Solutions are not the answer." - Richard Nixon