Starting to look into FT a bit more and I am currently reading the following document from VMware http://www.vmware.com/pdf/vsphere4/r40/vsp_40_availability.pdf this has already raised some more points for me that I didn’t realise such as the system needs to be certified as FT capable by the OEM.
Looking into this more I found out the the HP DL380 G5 and G6 or at least for the models I checked here>> http://snurl.com/q3c22 were not listed as being FT capable! I had realised the CPU’s needed to be certified for FT on this list >> http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1008027 previously but not the physical host. It has also been pointed out to me by @FrankDenneman on twitter that the ever popular blade server by HP the BL460 is also not supported.
I think the more I delve into this the more difficult it is becoming to see use cases with such a high amount of restrictions and limitations.
@FrankDenneman did a little more investiagting into this and has found the following utillity that can be used to check your hardware for FT compliance http://www.vmware.com/download/shared_utilities.html he also found in the following VMWare white paper http://www.vmware.com/files/pdf/perf-vsphere-fault_tolerance.pdf that VMware are using A Dell PowerEdge 2950 which is also listed as not supporting FT. So this looks to be just a case of waiting for the manufacturers to certify specific hardware. Fingers Crossed.