I noticed something weird on an Ubuntu Server 16.04 virtual machine running on VMWare ESXi 6.0.
The machine hosts a website running on Apache 2 that is exposed to Internet. Also it runs SSHd to allow us to connect for support.
I'm receiving calls from the owner of that website telling the site is unreachable. What I do to re-enable it is simply loggin-in using SSH and that's it, everything is accessible again.
Today I tried to see if the website is working and found it wasn't reachable, so I logged in to the VM, but also did a check on some logs our app registers on it, and found nothing was logged since yesterday. But after a minute logs started to be generated.
This looks like the machine enters into a paused/suspended state after a while and is re-enable by just loggin in again.