Details
You need two SAS LSI3444E host bus adapters (HBAs) for HBA redundancy. ESX Server does not recognize the second HBA when using two SAS LSI3444E HBAs on IBM x3650 type 7979, due to PCI resource allocation errors. These errors are the result of a system BIOS issue, where the first HBA is available but the second HBA is not available. The second HBA might fail to appear under Storage Adapters in the Virtual Infrastructure Client. Only one path is available to the shared SAS storage targets from esxcfg-mpath -l output and multipathing info in the VI Client.
Solution
If you experience PCI resource allocation errors, the configuration utility will fail to initialize. You might need to disable PCI devices or change the ROM execution space. The system ROM space is full and there is no more room for additional adapters that use ROM space.
Based on VMware KB 1004486
