[OpenAFS] Re: [OpenAFS-devel] Support for huge (really huge!) cell

[Jeffrey Hutzelman]

On Friday, November 05, 2004 19:29:18 -0500 Derrick J Brashear 
<shadow@dementia.org> wrote:

> On Sat, 6 Nov 2004, Ian Delahorne wrote:
>
>>> We plan to install a read-only AFS-DB-Server in every school too (makes
>>> at least 100). Will Ubik scale to this number of Servers?
>>
>> Ubik doesn't scale beyond three servers.
>
> Five, sire.

You certainly can have five dbservers.

The current Ubik voting code will work with up to 20 servers with a total 
of up to 256 interface addresses.  This number includes non-voting servers, 
which must receive beacons even though their votes do not count.  However, 
actually running with that many servers would be pushing the limits of the 
system somewhat.

As others have suggested, a cleaner approach would be to run separate cells 
at each site, with replicated volumes copied semi-manually between cells. 
Any given user would have a home directory in only one cell, which would of 
course be visible from any site, as long as there was connectivity to the 
user's home site.

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