Coda File System

Re: Coda and FHS

From: Dr A V Le Blanc <>
Date: Thu, 15 Feb 2001 06:55:51 +0000
"Minh" == Ha Duong Minh <> writes:
> Minh>   While I understand there are many advantages to have files
> Minh> under /coda, I have not found in the doc how to make this
> Minh> consistent with the File Hierarchy Standard.

On Thu, Feb 15, 2001 at 12:27:50PM +0900, Stephen J. Turnbull wrote:
> FHS is mandated for Linux distributions.  This makes interoperability
> of utilities much simpler.  But local admins do not have to conform if
> they have reason not to.  /home -> /coda/home seems like a good reason
> for varying from FHS to me.

You will usually find that the symbolic link such as
/home -> /coda/home is actually allowed by the FHS, as long
as you can reach the required object through the standard path.
I have set up systems in which /usr is in fact a link to
somewhere in /coda; obviously this means that you can't install
coda itself anywhere under /usr.  The real pain is tweaking any
Linux distribution to deal with shared /usr on a particular
client.  This is one reason why I feel the distributions and
both rpm and dpkg fail to support this kind of installation

> You might
> also want to do this for some of the caches (eg, TeX's fonts) under
> /var, but you wouldn't want to do it for /var itself.

Certainly not for log files or other machine-specific stuff.  But
it is possible to put an amazing amount into Coda.  One solution
I tried was to have a skeleton /usr with the commands needed before
Coda starts in it; when the root disk is mounted we have

     ln -snf /path-to-skel-usr /usr

and then after Coda starts, we can add the command

     ln -snf /coda/path-to-full-usr /usr

to the startup scripts; similarly when shutting down.

There is a tool which is part of AFS called package which (in an
awkward way) allows you to manage machines centrally by maintaining
symbolic links and local copies of files; you would need a more
sophisticated version with pre- and post- copy features for some
cases, but it's not that difficult to write.  With AFS I was
able to mount / nosuid, and to have all suid and sgid programs
in AFS.  With Coda you can put the suid programs there, but not
sgid, of course.  (Thus in the previous example, where /usr is
a link into /coda, /usr/bin/man may have to be a link out of /coda,
if it is a sgid program.)

These are among the issues that an installation which makes full
use of Coda (or of AFS) must investigate and solve.

     -- Owen
Received on 2001-02-15 01:56:10