"Recursive no;" implications?

[LuKreme]

If you set recursion no; in named.conf, you need to set the forwarders as well. Is there anything else that must be done so that DNS queries still work?

If you have master/slave servers you should specify allow-recursion for your subnet instead, right? I'd you do this, you don't need to set forwarders, yes?

And finally, can you specify a slave DNS against a CNAME or must it have a rDNS and an A record?

For example

  NS ns1.example.com.
  NS ns2.example.com.

Ns1.  A  12.34.56.789
Ns2   CNAME name.someothername.tld

Where the server at the CNAME doesn't have rDNS?