IBM 88554RU Installation Guide - Page 37

x455 Node A 1 32 32 x455 Node B 1 1 x455 Node C 23 23 1 x455 Node D 1 SMP 2 Scalability 3 ports Figure 1-12 Four-node partition The partition is powered on by turning on the primary node (Node 1). This will power on the other nodes. It is also powered off by turning off the primary node, which will power off the other nodes. Note: Powering on and off the other nodes will have the same effect, but this should always be done from the primary node. The three scalability ports on the back of the machine are used to interconnect the machines, and the Configuration/Setup utility is used to define the partition and members of the partition. The scalability cables can be up to 3.5 meters long. This restriction normally means that all members of a partition will be in the same rack. For properly configured two-node systems, one of the scalability port connections may fail at either runtime or boot time and the system will continue to operate properly. Runtime failures will be logged in the System Error Log. For properly configured four-node systems, one of the scalability port connections may fail at runtime and the system will continue to operate properly. Failures will be logged in the System Error Log. Boot time scalability connection failure results in each node booting to the EFI shell independently. Below are the maximum supported configurations for one-, two- and four-node partitions. Table 1-5 Comparing one-node, two-node and four-node configurations Component 1 node 2 nodes 4 nodes Itanium 2 processors 4 8 16 Chapter 1. Technical description 23