You may have a look in the Apache logs what happens around that time:

Maybe there is an attack or web security scan running at that time? If there is a CPU spike, I would expect something in the logs. And, yes TAC can probably even better find out what's going on and if it's harmful or needs to be addressed.
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Herman Robers
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If you have urgent issues, always contact your HPE Aruba Networking partner, distributor, or Aruba TAC Support. Check
https://www.arubanetworks.com/support-services/contact-support/ for how to contact HPE Aruba Networking TAC. Any opinions expressed here are solely my own and not necessarily that of Hewlett Packard Enterprise or HPE Aruba Networking.
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