Re: Networkhood file system

doctor@fruitbat.org
Sat, 29 Aug 1998 00:22:05 -0700 (PDT)

DAVID BALAZIC stated ...
> David Woodhouse <David.Woodhouse@mvhi.com> said:
> [...]
> > However, that's the easy bit - how would we handle authentication? It's
> > not possible to just bring up a login window when the user tries to
> > change into a remote directory. Furthermore, once we have managed to
> > obtain a username an password for the remote system, what permissions do
> > we give to other users than the one who logged in?
>
> The tool ClearCase ( avaliable for Solaris , HP-UX .... )
> offers per user ( or per process ) filesystems.
> The file-system look differently for diffeent processes.
>
> Multiple users can access the "same" files , but having different access right.

As a user of ClearCase at work, I just want to add that you pay a very,
VERY high cost in CPU, Network and local disk space for that ability.
Atria implemented their own filesystem (called Multiple Versioned File
System (MVFS)) which hooks into the kernel as a kernel extension (under
Unix implementations). The implementation is such that each user has a
"view" of the filesystems being accessed. These views are maintained
using a combination of local disk and remote lookup for all filesystem
accesses. Even on high end machines the speed is painfully slow. If you
think NFS is slow, then you don't even want to considder the speed of a
ClearCase filesystem. IMHO, there are better ways of doing this.

> Just my $0.02

Mine too...

-- 
Peter A. Castro (doctor@fruitbat.org) or (pcastro@us.oracle.com)


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