[OpenAFS] Re: AFSDB dns lookup

Jeffrey Hutzelman jhutz@cmu.edu
Mon, 03 Apr 2006 13:30:22 -0400

On Monday, April 03, 2006 01:22:16 PM -0400 Pedro Perez 
<pperez@opensourcetechnologies.net> wrote:

> IF /etc/nsswitch.conf could contain a line like this:
> afs: dns files
> OR
> afs: files dns
> things would work just like DNS. Could this be a possible solution?

Not really.  It turns out that the innards of the name service switch are 
completely different from one operating system to the next, and not very 
extensible in this direction.  Doing what you describe would require 
extending the 'files' and 'dns' nss backends to understand the "afs" 
database, which can't be done without replacing the modules the OS vendor 
provides (if they're even provided as modules, which is not required).

Also, a "solution" to what?  We could probably make it possible to tell the 
cache manager to use DNS first, but what would be the point?  If you want 
to rely primarily on the DNS for locating AFS servers, then your CellServDB 
should be mostly empty, containing only entries for cells where the 
nameservers are unresponsive, or hand out incorrect data, or where you 
otherwise want to override the data handed out in the DNS.

-- Jeffrey T. Hutzelman (N3NHS) <jhutz+@cmu.edu>
   Sr. Research Systems Programmer
   School of Computer Science - Research Computing Facility
   Carnegie Mellon University - Pittsburgh, PA