email redirection question

[Jerry Feldman]

On Thursday 07 September 2006 10:26 pm, Ben Scott wrote:
> On 9/7/06, Dan Coutu <coutu at snowy-owl.com> wrote:

> > ... or share the /var/spool/mail directory between the two systems.
>
>   My recommendation is to never do this.  Unix has somewhat... quaint
> ideas about file locking, and is very inconsistent in their usage.
> I'm told a shared mail spool *can* be done, if you get all the planets
> lined up right (i.e., used a carefully selected set of software, which
> all agrees on a locking mechanism, make sure nobody uses any other
> software, make sure nobody can change the software config with regard
> to locking mechanism, use the right NFS parameters, make sure the NFS
> server, NFS client, C library, etc. implement it all correctly,
> sacrifice a goat, etc.), but even then, all it takes is one mis-step
> and everything goes to hell.
I've seen sharing of the  /var/spool/mail directory work reasonably well, 
especially in a situation where user directories are also exported via NFS. 
NFS has been used very successfully to provide directories shared between 
different client systems. We currently have users home directories exported 
to Linux (RHEL 4, SLES10, Debian), HP-UX, Tru64 Unix, FreeBSD, and Open VMS 
with clients on x86, x86_64, and IA64. We don't permit email from those 
systems, but there is a very heavy use of NFS between those systems. 

Generally, it is important that the file locking mechanism is consistent.

-- 
Jerry Feldman <gaf at blu.org>
Boston Linux and Unix user group
http://www.blu.org PGP key id:C5061EA9
PGP Key fingerprint:053C 73EC 3AC1 5C44 3E14 9245 FB00 3ED5 C506 1EA9