[Beowulf] Re: quick and dirty method for starting job on another node?

[David Mathog]

> This brings up an interesting point. How many people are running with
> their entire cluster exposed to the big bad internet. From thinking
> about it for a minute I would simply expose the head node to the
> network/internet and everything else would be a royal pain to route a
> packet to.

Most probably are wired as you described.

However one of the original uses for dolly (the program
from which nettee was derived) was to reimage a
lab full of workstations, and those PCs would
probably be sitting out on the open net.  Using nettee
to write a partition is relatively safe even there
in that the program keeps track of the number of bytes
written so that even if a hacker managed to inject
something into the data stream the up stream node would
find out when the compromised node returned its byte count. It
would be a bad idea to then boot the machine(s) with incorrect
byte counts.  On the other hand, running nettee as a pipe for
commands would execute whatever a hacker could inject into
the data stream immediately, which could be really, really bad.

Regards,

David Mathog
mathog at caltech.edu
Manager, Sequence Analysis Facility, Biology Division, Caltech