NFS in a heterogeneous environment

[roy at phri.UUCP]

	We currently have a bunch of Sun-3's running 3.1FCS and a Vax
running 4.2BSD, soon to be upgraded to Mt Xinu's 4.3 w/NFS.  Eventually we
might be adding other Unix machines to the net, all running NFS.  We run a
pretty open system, with the idea being that anybody can sit down at any
available device (be it a Sun workstation console, or an ASCII terminal on
a serial line to either the Vax or a Sun, or a dial-up line) and see as
uniform an environment as possible.  I'd like to hear from people who have
experience setting up heterogeneous NFS systems.

	Some of the problems seem pretty straight forward to solve.  For
example, different machines mount /bin, /usr/bin/, /usr/local/bin, etc.
(and /etc :-)) from a file server of the same type.  What about home
directories?  Do you give people a $HOME on each type of machine?  It seems
like we'll have to do this, if for no other reason, then because we run 2
versions of emacs, and the format of the dot-emacs files are different on
the Vax and the Suns.  We *could* hack up everybody's dot-login files to
check the machine type and make the right symbolic links, but that seems
pretty grotty to me.  Besides, it would be really nice to be able to tell
somebody to look at "~roy/whatever" without having to worry about which
"~roy" I mean.

	How do you deal with big data bases?  We have some rather large
shared data bases (Genbank and related stuff is about 50 Mbytes, for
example) that I'd rather not replicate if I don't have to.  Since most of
the data base is ASCII, there isn't much problem there, but what about
binary index files?  One solution would be to share the ASCII parts and
have the binary parts be symlinks to the real files in /local/lib/binary,
and mount the appropriate /local/lib/binary depending on which machine you
are on.  Does this seem reasonable?  I'm hesitant to get into a situation
where data bases are scattered all over the universe with billions of
symlinks tying it all together -- sounds like an administrative nightmare.
Can anybody think of a better way?

	What about people doing program development?  It would be nice to
be able to have a single source (possibly with #ifdef VAX/SUN lines in it)
which you could just run make on and have both binaries made automatically,
and have the right binary chosen for execution depending on which machine
you are on.  Any suggestions for easy ways to set that up?
-- 
Roy Smith, {allegra,cmcl2,philabs}!phri!roy
System Administrator, Public Health Research Institute
455 First Avenue, New York, NY 10016

"you can't spell deoxyribonucleic without unix!"