nullfs mount ignores readonly flag

[David Beck]

OK. Thanks for the advise.

[I know this should go to another newsgroup...]

The idea was to use nullfs for jail filesystems, so I don't need to 
duplicate files as many times as jails I have.

This had two advantages to my opinion:
   - the jail would share system executables on a readonly filesystem, 
so system upgardes would be easier.
   - also I thought that this would increase the level of security in 
jails.

If not nullfs would you recommend NFS in a similar setup? Do you see an 
other solution that works better?

Thank you very much,

   David.

Simon 'corecode' Schubert wrote:

David Beck wrote:

Would that fix mean that the no-setuid, no-exec and other flags will 
work as well?

Regards, David.

Matthew Dillon wrote:

   I expect there will be things that need working on.  That's one of
   them.  Hmm.  We will probably have to hold the namecache entry for
   normal files and use the namecache's mount point to check for the
   read-only filesystem status.  No biggy (we already do this for    
directories to maintain the CD path), but it may take a few days to
   fix.

Talking of nullfs:  I'd strongly advise not to use it in its current 
state in production.  There are many things that need to be resolved 
first.  See my post on kernel@

cheers
  simon