You've got a script or process somewhere (internally or externally) that's calling for a graceful shutdown. Where that's occurring, no idea, but that appears to be what's happening. This doesn't look like ESXi is just suddenly deciding to go to bed.

VMKAcpi: 259: Power button pressed

 This is odd. Is there someone else that might be pressing the power button? 

I'm not sure if that line literally means, "a human finger pressed the power" or if the system got sent SIGTERM as a graceful shutdown request.

any luck with this. we are getting the same power button pressed line but no one pressed the power button.

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VMware version, build, brand, type and model of the physical Server.

Does this correlate with any other events in the environment? You don't have DPM on do you?

DPM is not enabled. No it doesnt correlate with anything i could find. i checked all the logs and there is no indication of a power off request coming from out of band management, the console, the shell, dcui. I was certain the power button was pressed because we did a test with someone pressing the power button and it matches the logs exactly. but security says they checked the cameras and no one was near the server.

thanks for the response.

Sorry I couldn't help more. One last thing I would check for would be an actual physical short on the server main board causing this.

Upgrade ESXi to 7.0.3 
Upgrade iLO or iDRAC, BIOS. Check firmware and driver versions. 

During the upgrade to vsphere 7.0.1 did you use a customized vendor ESXi ISO? If not - use next time