Multirack Cabling Overview
You connect multiple SuperCluster M8 or SuperCluster M7 systems together using IB switches that are installed in the racks.
All SuperCluster M8 or SuperCluster M7 systems have two IB switches, a leaf switch 1 in U18 and a leaf switch 2 in U24. Depending on how the system was ordered, a third IB switch (spine switch) is installed in U1. If the spine switch is not present in the system, you must install a spine switch before you can connect another SuperCluster M8 or SuperCluster M7 system.
IB switches use standard IB cables with QSFP connectors. The procedures in this section assume that the racks are adjacent to each other. If they are not, then longer cables might be required for the connections.
In a single rack, the two leaf switches are interconnected using seven connections. Each leaf switch has one connection to the spine switch as shown in this graphic.
When you connect multiple racks, some of these factory IB switch cable connections must be reconfigured as described in Connect Additional SuperCluster M8 or SuperCluster M7 Racks.
Note - For information about using Subnet Manager to manage the IB switches, refer to this section http://docs.oracle.com/cd/E50790_01/doc/doc.121/e51951/components.htm#DBMMN21291 in the Oracle Exadata Database Machine Maintenance Guide.