Re: PVM 3.4.2

[Drake Diedrich <Drake.Diedrich@anu.edu.au>]

On Fri, Oct 08, 1999 at 02:19:47AM +0100, Mark Brown wrote:
> On Thu, Oct 07, 1999 at 11:28:49AM +1000, Drake Diedrich wrote:
> 
> >    Another change is the /etc/alternatives/pvm-rsh alternative link.  PVM
> > can now use ssh (and krsh presumably) to initiate pvmd connections. 
> 
> Could you perhaps change the name to "beowulf-rsh" or something so that
> all the clustering libraries could use it please?  I have been meaning 
> to get around to implementing a similar thing for MPICH (especially
> since I now have a wishlist bug for it) and I imagine LAM could use it
> too.

   I was hoping the remote shells would provide the alternatives themselves,
and I could then point pvm-rsh to that.  I was expecting the rsh-client
breakup to include a remote-shell alternative.  Note that there is no
/usr/bin/pvm-rsh file.  It's /usr/lib/pvm3/bin/rsh.  If you use it you'll
need to add a dependency on pvm no matter which directory I put it in. You
probably don't want to do this.  I don't even like doing it, I just got
desparate.  :)  I suggest reassigning the bug to rsh-client and ssh so that
at least it's not counted against you.  Eventually they'll cave in and make
us a link.

  If you aren't content to wait what I recommend is that MPICH and LAM each
create similar alternatives pointing to /usr/bin/rsh for now.  When the
remote shells start providing one of their own you can then either switch to
the new alternative link or change the default from /usr/bin/rsh to
/usr/bin/remote-shell (or whatever the link point is).  Keeping your private
*-rsh will make it possible for PVM and MPICH to use different default
remote-shells if the admin overrides /etc/alternatives/*-rsh.

What I did was modify the internal pathname of the rsh binary and stick the
following in the postinst and prerm files.  Modify accordingly.
Note that creating a link to /usr/bin/rsh in pvm's files should be a policy
violation.  If they get wind of this it will probably become one, just
refile those against rsh-client and ssh as well.  :)

pvm.postinst
------------
#!/bin/sh
set -e
update-alternatives --install /usr/lib/pvm3/bin/rsh pvm-rsh /usr/bin/rsh 10
#DEBHELPER#

pvm.prerm
---------
#!/bin/sh
set -e
update-alternatives --remove pvm-rsh /usr/bin/rsh
#DEBHELPER#