At plan9, all network database contains in /lib/ndb, also DNS data.
Edit /lib/ndb/local with ed, sam or acme. Add follow lines for DNS.
dom=yourdomainname.net soa= refresh=3600 ttl=3600 ns=ns.yourdomainname.net ns=ns.somewhere.net mb=your@yourdomainname.net mx=mx.yourdomainname.net pref=10 dom=ns.yourdomainname.net ip=10.1.1.1 cname=other.yourdomainname.net dom=real.yourdomainname.net