Method 1 - Ethernet Topology For Multiple-Frame Sp System - IBM RS/6000 SP Handbook

You have to set up your SP Ethernet routing so nodes on one Ethernet can
communicate to nodes on the other network. You also need to set up your
network mask so that each SP Ethernet is its own subnet within a larger network
address.
Multiple frame systems
For multiple frame systems, you want to spread the network traffic over multiple
Ethernets, and keep the maximum number of simultaneous installs per network
to eight. You can use the control workstation to network install specific SP nodes,
which will be the network install servers for the rest of nodes.
There are three ways to accomplish this.
1. The first method uses a control workstation with one Ethernet adapter for
each frame of the system, and one associated SP Ethernet per frame. So, if
you have a system with four frames as in Figure B-7 on page 400, the control
workstation must have enough I/O slots for four Ethernet adapters, and each
adapter connects one of the four SP frame Ethernet segments to the control
workstation. Using this method, you install the first eight nodes on a frame at
a time, or up to 32 nodes if you use all four Ethernet segments
simultaneously. Running two installs will install up to 64 nodes. Figure B-7
shows an Ethernet topology for this multi-frame system.
Figure B-7 Method 1 - Ethernet topology for multiple-frame SP system
400 RS/6000 SP and Clustered IBM ^ pSeries Systems Handbook
Ethernet 1 Ethernet 2 Ethernet 3
CWS
Ethernet 4