IBM 71413SU - System x3950 M2 Reference page 10

Currently, only one-node and two-node configurations are supported, although plans are in
place to support three-node and four-node configurations in 2Q08.
The scalability cabling needed to form a two-node complex is shown in Figure 4.
x3950 M2
x3950 M2
(primary)
Figure 4 Cabling for a two-node configuration
Two 3.08m cables are required, as shown in Figure 4. The cables are supplied as follows:
One cable is part of the ScaleXpander Option Kit, part number 44E4249, as described in
"IBM ScaleXpander Option Kit" on page 6, for use with x3850 M2 servers.
One cable is included with x3950 M2 servers (not with x3850 M2).
Note: Connectivity for three-node and four-node configurations is not supported until
2Q08. When this support is announced, this document will be updated with cabling
information.
The following key points relate to scalability cabling:
The x3950 M2 comes with a new cable management arm that makes installation and
management of the cables easier. The ScaleXpander Option Kit for the x3850 M2 ships
with this new arm to replace its standard cable management arm.
The scalability ports cannot be used as high speed interconnects for clustering purposes.
Use the integrated Gigabit Ethernet controller instead.
The connections do offer redundancy. If a connection is lost (for example, if a cable is
unplugged), there will be an indication on the light path diagnostic panel showing a link
failure, and the server will disable the failing port and switch traffic to the remaining path.
There will be a slight performance degradation in this mode. After the cable is reattached,
the server will re-enable the path and clear the error from the light path diagnostic panel.
In multinode configurations, the inbound communication between each node now is
handled by the scalability cables, and not by the RSA II Ethernet ports (as it was with the
x3950).
Partitioning
Partitioning
systems. You can then install an operating system on a partition and have it run
independently from all other partitions.
The advantage of partitioning is that you can create and delete partitions without having to
recable the complex. The only requirement is that partitions be formed on node boundaries.
The interface where you set up and maintain partitions is an extension of the Remote
Supervisor Adapter II Web interface. It is used to create, delete, control, and view scalable
partitions.
10
IBM System x3950 M2 and x3850 M2 Technical Introduction
Two-node configuration
Port 1 Port 2
Port 1 Port 2
is the concept of logically splitting up a multinode complex into separate
RSAII
Port 3
RSAII
Port 3
Ethernet
network
3.08m cable