This happen today while patching Banner.
VMware ESXi 6.0 host fails to detect local disk after patching
https://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2120539

I had to revert Banner Warsaw ESXI server after trying to update it today.
Reverting to a previous version of ESXi
https://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1033604

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From VMware Support

You can update the host to the latest 6.0 U2 version by downloading the HP custom ISO here https://my.vmware.com/group/vmware/details?downloadGroup=OEM-ESXI60U2-HPE&productId=491 and you can then create a baseline using this ISO to update your hosts using update manager. This custom ISO will not cause the issue in kb 2120539 as this issue is only seen on hosts that had a custom HP image installed that were then updated using a later VMware image. Here is an overview of the steps to follow:

Once you have the ISO downloaded You can select the host in the vsphere client go to Update Manager—-> Admin View——>ESXI Images —–> Import ESXi Image (During the import you can create a baseline) ——-> Switch to compliance View ——-> Attach Baseline ——-> then you can either stage first then remediate or just go straight to remediate.
Of course if you do not have DRS running make sure that the Host has no VM’s on it and it is in maintenance mode beforehand.