[Beowulf] running out of rsh ports

[Greg Lindahl]

On Wed, May 03, 2006 at 12:16:03PM -0500, Bruce Allen wrote:

> rsh typically uses ports in the 513-1023 range.  With a 640 node cluster 
> we are running out of ports.  This leads to messages such as:
> "rcmd: socket: All ports in use"
> 
> Are there any standard solutions to this other than 'use ssh'?  We already 
> have net.ipv4.tcp_tw_recycle = 1 in /etc/sysctl.conf

As another amusing example of this, PBS before the tm interface
(~1999) used a low port to contact Moms, so it was easy to run out.

So I lowered the TIME_WAIT on the PBS master node.

-- greg
(don't try this at home unless you're a trained expert in network perversions...)