If its just failed login attempts you could either configure CSF to block IP's after only a couple failed logins or use cPanel's built-in cPHulk Brute Force Protection. Have you done anything else to secure your server?
I am concerned as I get several emails containing this like this:
Large Number of Failed Login Attempts from IP xxx.xxx.xxx.xxx
I'm trying to stop it, as obviously, I don't want anyone gaining access to my server.
Any tips for making sure the server is really secure?
All the best,
Wow... Where should I start on this topic? I am guessing since your having issues with a large number of failed login attempts then I would question the current security measures in place besides failed login attempts. Yes, failed login attempts are going to happen from valid clients, yourself, and staff. The first thing you would want to do is change the number of failed login attempts until a ban is put into place by cPanel/WHM. If its a bunch of Brute Force attacks on the server shell then I would suggest installing a brute force detection software.