ESX Server 2.5.5: System with Mixed 4Gb and 2Gb QLogic HBAs Missing COS Device Files for SAN LUNs After Boot
Details
A system that contains both 4Gb and 2Gb QLogic Fibre Channel HBAs that are configured in Shared and VMkernel modes, respectively, might fail to create COS /dev/sd* device files for SAN LUNs after boot.
Solution
You must use vmkpcidivy to configure all QLogic HBAs to operate in either Shared or VMkernel modes (but not a mixture of both), then reboot.
As a temporary workaround, you can create the COS /dev/sd* devices files by manually re-scanning the SAN.