[OpenAFS] Cleaning up the client cache

Frank Burkhardt fbo2@gmx.net
Sat, 17 Jul 2004 17:56:57 +0200

On Fri, Jul 16, 2004 at 01:39:01PM -0400, Jeffrey Hutzelman wrote:
> On Friday, July 16, 2004 09:58:06 -0400 Jim Rees <rees@umich.edu> wrote:
> >  Is there a chance to delete the cache on demand (something like
> >  'fs cleancache') without stopping the cachemanager?
> >
> >Nothing other than "fs flush" but maybe there should be.
> No; fs flush doesn't remove data from the cache; it just clears metadata so 
> the client will be forced to contact the fileserver the next time it wants 
> that data.
> You can generally convince the cache manager to remove data from the cache 
> by temporarily setting the cache size down to a very small size.  Of 
> course, even that only _frees_ the blocks on disk; it doesn't zero them.

Hmm ... that's not enough :-( . I think my approach was completly wrong. The
idea was to delete the cache (in a way that it can't be restored - not just
releasing chunks) whenever a user logs out. Due to other users could still
be logged it, there's no chance to stop the afs-client temporarily to delete
its cache with a seperate program. Additionally I would have to overwrite the
swap file with zeros - maybe there were some critical /tmp-files, too.

Even that isn't really secure because a local root could easily remove those
security measures. -> I'll give up that idea.

Thank you very much for your help,