Multiple zones pointing to same zone file

[Jay Ford]

On Tue, 19 Oct 2010, John Wingenbach wrote:
> I know that per Mark Andrews that named does not support having multiple 
> zones pointing to the same zone file.  I can understand the issue if named 
> does not support it for a slave server.  What about for a master server?  Are 
> there any issues with named supporting that?
>
> I would assume that whenever the zone file is changed, notifies for each zone 
> utilizing that file would be sent out.  Is that correct?  Does named support 
> that?  If not, are there any plans for named to support having multiple zones 
> utilizing the same zone file?
>
> I would prefer to make sure that we are using named in a supported fashion 
> despite that it has been working this way. :)

"support" might a little strong, but it won't cause problems for non-dynamic
master zones like it will for slave zones.  Dynamic zones will break if 
you have them share files, just like slave zones will break.

Note that notifies are sent when the zone is (re)loaded, not when the 
associated file changes.  You'll have to reload each zone which is based on 
the file after you change the file.

This (along with other things) gets more interesting when you start signing
the zones for DNSSEC, but you might be able to play symlink games with the
unsigned file names to deal with that.

________________________________________________________________________
Jay Ford, Network Engineering Group, Information Technology Services
University of Iowa, Iowa City, IA 52242
email: jay-ford at uiowa.edu, phone: 319-335-5555, fax: 319-335-2951