Hi you can get hardware specific versions of ESXi (IBM/Dell/HP) which give better support/integration with the underlying hardware - but as I see the advantages are outweighed by the disadvantages.
As I see it:
Pros:
Better intergration with hardware
hardware specific CIM
Cons:
Generally the hardware specific versions are more out of date than the generic
If you use VMware update manager it will, presumably, install the generic version.
If you cannot use update manager Then you must re-install an updated version which means re-configure the host from scratch (if you do not have Enterprise Plus with host profiles)
Regards
Bill
Actually Update Manager should just update the VMWare Components and not change any of the hardware specific software - Also anything that is installed with hardware specific ESXi you should also be able to obtain from the hardware manuifacturer for installation into the 'Generic' ESXi because both utilize the same underlying code for the hypervisor.
If you don't want to use a OEM custom image, there may be an offline bundle you can add to a generic ISO install via VUM.
HP for example:
http://h18000.www1.hp.com/products/servers/software/vmware-esxi/offline_bundle.html
Without the hardware specific CIM providers your have a very much reduced view of your hardware. You will not likely get notice of disk or array failures especially. You will not be able to monitor and recieve notification on those types of failures from within vCenter. Make sure your specific model is supported by the manufacturer for ESXi otherwise use the generic install.
