Banning IP’s would be a long job you will most likely find that there are multiple hackers trying to get into your site and exploit it.
My Advice
1. if you have had register_globals = on switch it off.
2. If you have been compromised check for any new files or modified files in the past week or two *.php
Most likely the hackers will drop in a back door .php or modify something existing to be able to get back in
3. If you have been compromised and would like to be extra safe download your site as a backup and reupload a fresh version of MODx and reconnect to your database.
4. Change your database password.
On Onesmarthost many sites have had hackers attempt to exploit reflect but because register_globals = on we are all safe.
We are also running daily checks on new .php files just in case for a short time.
Looking at the logs the hacks are coming from many IP’s and Countries, most likely junior hackers trying out a new exploit which doesnt work here
I also download my log files each week and import them into excel makes it much easier to view and from that you can easily spot any possible breakins.
Aaron