Category Maximum populationStorage Sled Up to seven Storage sleds can be populated in the enclosure.NOTE: One compute node must be present and it must be mapped to a storage node.One Fabric-C SAS IOM must be present and powered ON.I/O Module Only Brocade and SAS IOM are supported in Fabric-C.Only one type of IOM can be offered in Fabric-C (Fibre Channel or SAS IOM, not mixed).Only one type of switch can be offered in Fabric-B (HPCC or Ethernet).Two Fabric-C SAS IOMs must be installed if the enclosure contains a Storage Node.Mix Speed of pass-through in same fabric is not enabled.Mezzanine cards If the enclosure contains a storage node, Fabric-C MiniMezzanine card (HBA330 or Jumbo PERC) must be installedin one compute node.Dual Port or quad port mezzanine cards must be installed for redundant IOM/Pass-through configurations.The second processor must be installed on the compute node to support Fabric-B Mezzanine / IOM and Fabric-CMezzanine / IOM.PSU redundancy and population rulesThe number of PSUs required depends on the enclosure configuration and redundancy required. The minimum requirement is two PSUs.The enclosure supports one of the following redundancy modes:• No redundancy: This mode does not support any PSU redundancy and is used in situations where the enclosure does not have enoughnumber of PSUs to support the installed configuration.• Grid redundancy: This mode provides for PSU redundancy at the grid or branch level. For grid redundancy, PSUs should be populatedin the following order: 1, 4, 2, 5, 3, 6. Supported configurations for this mode include 1+1, 2+2, and 3+3.• PSU redundancy: This mode provides for redundancy at the PSU level. The supported configurations for this mode include 1+1, 2+1,3+1, 4+1, and 5+1.NOTE: For high-line AC power, the 5+1 configuration is unavailable as the chassis cannot draw more power than four PSUscan deliver.• PSU pairing: This mode supports power input from two different power grids. The PSUs are connected such that PSUs 1 to 3 areassociated with one grid, while PSUs 4-6 are associated with the second grid. The power sockets on the rear of the enclosure are setup as three plugs on each side of the chassis for connectivity to the PDUs of the rack.NOTE: The PSUs support the Rapid-ON feature. This feature enables a PSU to go into sleep mode while the enclosure powerconsumption is low and the partner PSU meets all the power requirements for the enclosure. This enables efficient powerutilization when the overall enclosures power requirement is low. The partner PSU can wake the PSU from sleep mode bysending a WAKE signal when the enclosures power requirement increases.NOTE: For more information about the supported PSUs, see Technical specifications.Table 11. PSU population rulesPSU count Population order2 1, 43 1, 4, 24 1, 4, 2, 5Technical specifications 55