I have VM-Instances, working well with ubuntu 16.04, LAMPP and Wordpress since Dec 2017.
But since yesterday 25/04/18, when I was building wordpress in wp-admin, suddenly Wordpress gave error message "Error establishing a database connection". Immediately I checked GCP-console and access ssh. I suspect there was a problem with mysql (before this ever happened), so I rebooted the server and the server returned to normal, but only a few minutes. Then a database connection error occurs again. This time when I access SSH via console, it always comes out error message
"Connection Failed - An error occurred while communicating with the SSH server. Check the server and the network configuration".
If I open the website was always out message "This site can not be reached". I've tried checking firewall configurations etc, but did not find any weirdness (because I did not make any changes).
so from yesterday to today, I can not access server in browser or via SSH. Server down / offline.
How to solve a suddenly problematic server like this?