Switch mode's longer IB distances are supported only when specific guidelines are followed. As you read this topic, you will find it helpful to refer to the diagram in Switch-Mode Supported Topology.
Topology and switch considerations:
A maximum of two sites (datacenters) is supported per switch-mode topology.
Within a switch-mode topology, a maximum of four virtualization switches is supported, two per datacenter so that each datacenter has redundant switches. Each virtualization switch must contain at least one IB LR module and the IB LR modules must be connected to the IB LR modules in the other virtualization switches.
Module connectivity considerations:
Link connectivity: Both sides of the IB LR links must be connected to the same out-of-band (OOB) management network and be managed by a single admin authority that manages both sides of the IB LR link.
Port connectivity: IB LR module ports can be connected to other IB LR module ports only. Generic QSFP-to-QSFP connectivity is not supported between two IB LR modules.
Host server considerations:
Switch mode is supported for stand-alone, rack-mount servers.
Hosts must be connected to the Oracle InfiniBand IS2-46s (leaf switches). No other intervening IB device(s) can be used to connect the server HCA ports to the virtualization switch's external IB ports.