How to find out the cause of 100% load on the VDS server?

Question

linux

Good afternoon!
Screenshot from htop

100% server load.
Support says fail2ban is the cause:
"As you can see in the output of the htop utility, the Fail2Ban software is doing the load."
I don't quite understand how they figured this out.
How to understand the cause of the load on the server and eliminate it?

Answer 1

hire an admin

Answer 2

In any incomprehensible situation, first of all, look at the logs.
You have a hell of a lot of Apache threads in the running state, a quarter of them in the D-state. To them you have a database. All this on two cores and two gigs of RAM. At the same time, the swap is already packed to capacity, and the free operatives are 300 meters for the page cache.
If ssh responds, then stop Apache and look at the request logs, someone is probably either brute or DDoS-it, or the site owner made another hole in the site engine and did not update it in time. The site still hangs in the eternal "Waiting for a response from the server", so you won't lose much, and the resources for troubleshooting will be freed up.

Answer 3

apache2 loads the most.

Answer 4

Judging by the screenshot, there are many calls to the web server and, consequently, to the DBMS. More cannot be said from the information provided.