I have this weird issue right now that even immediately after changing root password I can't login to the server. In fact I can't login to anything.
This has happened before to me months ago and the server kinds of restore itself to normal after a few hours.
But this shouldn't be happening.
Has anybody experienced this before?
This can be off different possibilities.
1. Your local ISP ip may be blocked at cpHulkBruteForce at your server - As cPanelMichael said, try stopping the cpHulkBruteForce temporary and recheck.
To do so, try in console # /usr/local/cpanel/etc/init/stopcphulkd or through WHM as root => cpHulkBruteForce => Disable cpHulkBruteForce
2. Your local ISP ip might be blocked in your server's firewall. If you're using CSF as cPanel server's firewall, try stopping csf temporarily and check with your ip address in the csf firewall's deny list whether actually blocked ?
3. If you still can't login to the server from different ip address, then probably your server is under
RED Alert !!! Suspect Hacked. Check with the Server administrator and remove the hacker and make your server more secure.