Coda File System

Re: coda looses group ownership

From: <>
Date: Wed, 28 Feb 2007 13:58:09 +0100
Hi Enrico,

On Tue, Feb 27, 2007 at 06:58:07PM +0100, Enrico Weigelt wrote:
> what exactly does "globality" mean ?

It means many things, all of them important and mostly unique for Coda
compared to other file systems.

Globality means among other things that on any client computer
in the world, connected to Internet and running Coda
it is possible to access arbitrary files, given privileges
granted to your account at the corresponding realm and your knowledge
of the corresponding secret (of course accounts and secrets are different
for different realms).
The point is - no administration of the _computer_ is required.

(Another important aspect of globality is file access paths being independent
of the client administration.)

With other words, globality implies functionality across administration
domains. With Coda it is _primarily_ different entities who administrate
servers compared to clients as any client computer is administrated by 1 entity
but can access all realms in the world, which is quite a bit :)

Your intentions of mapping between local and global uids
are incompatible with such functionality.

At the same time any "compatibility" with traditional setups is
harmful as it encourages wrong practices.

Coda offers an approach where a lot of problems in system administration
simply do not exist, problems you are otherwise solving every day
in the traditional installations.
(like synchronization of uids and gids across computers on a campus)

I could go into details and discuss different scenarios and such, but this
list is not a right place, neither am I going to write down a course
in advanced system administration :)

The matter is - traditional system administration practices are limited
and do not scale well. Enforcing by tradition the wrong features -
on the only file system free from old flaws - is harmful, in several ways.

I might compare that to the situation with different national character
encodings versus Unicode/UTF. Each old installation worked "well" with some
kind of non-unicode. It is hard to accept that one must replace a lot in the
system to switch to unicode, without any immediate gain. Yet there is no other
way to ensure that you can use all alphabets, even simultaneously when

You are in the situation when one believes one never needs other alphabets,
kind of.

Best regards,
Received on 2007-02-28 08:00:21