I want to share a performance problem on a VPS (also good for dedicated)
I'm running on a VPS Quad Core 4 Gb
I saw that a bot tried to enter the RDP, without success.(every second a new attempt, maybe more!!)
So the login process under Windows is ressource consuming. (going until 100% when queried like this)
In other words that was a brute force attack ( I saw 4 IP's from different continents)
I installed a IP blocker (3 attempts --> block IP for 1 day (port 3389)
Yes and it resolved my problem.
I recommand:
If you don't need RDP stop the service.
Or use RDP only via secured VPN-tunnel with restriction on IP
Change the administrator login name
Use not a strong but a very strong password
Use a IP-Blocker fir RDP (also for other protocols , or against Blog-Spam)
Check the settings of your Firewall (windows)
Check your Windows Logs regulary (also when everything is fine)
Remove all service/role/protocol who is not used (smtp, snmp, pop, imap)
Update your server when updates are available, don't wait...
hope this can help