Security with clusters

[Ricardo Sousa <rjsousa@softhome.net>]

Hi.
Lately i am doing some works about Clusters (especially beowulf), and i
start to consider putting it (to really know how it works) in my
network.
All the stuff about DSM (Distributed Shared Memory), and making the OS
to distinguish the user from system processes among other things make me
though: and about security?
Because of lack of computers, i (*think*) will put my gateway and the
other machine act as client/server cluster (respectively).
What security risks can/will i pass?

Thanks in advantage,
Ricardo