I upgraded from esxi 6.5 u2 to esxi 6.7 u3 ( 15160138 ) last week. vmtools version 11.0.1 and hardware version 15 are now on virtual machines . something caught my attention. Access problem came from some machines and when I checked, I saw that network cards are not connected. I'm not sure, but it looks like network Cards are breaking off by themselves. I couldn't find the common features of the servers. Is there a mistake in this esxi or etc.. version, or is it a coincidence?