[Beowulf] running out of rsh ports

[Joe Landman]

David Simas wrote:

> Except that it probably won't help with the problem, which I'm
> guessing is caused by a given host attempting more than 1024
> RSH connections to a given server in less than TCP TIME WAIT
> seconds (minutes, whatever).  If the original correspondent

Actually it handles exactly these cases.  The FANOUT variable lets you 
indicate the appropriate parallelism for rsh.  I believe pdsh is in use 
on the big clusters ( > 1024 nodes at the national labs )

> doesn't want to use SSH for RSH, which would fix things 

True, and you can use ssh with pdsh.  Or rsh.  With no syntax change to 
the end user.

> SSH isn't restricted to low-numbered ports, he could try to
> re-implement his application in MPI.

The basic question a few of us have is exactly what is Bruce and team 
doing that is causing them to run out of ports.  Once we see this, we 
can stop guessing and make better/targetted suggestions.




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Joseph Landman, Ph.D
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