all editions of ubuntu have no ports open default when you install so you don't have to rush to get it secure.
(NOTE:for denyhosts to work you must have iptables installed)For servers i would suggest denyhosts, it is designed for ssh/ftp login attempts, you can specify how many login attempts until a temporary ban(you specify ban time) and how many bans until a permanent ban. all of those option can be set in the denyhosts configuration file.
to get denny hosts simply type in the command prompt
sudo apt-get install iptables(only if not installed)
sudo apt-get install denyhosts
Lokkit, a GUI firewall configurer that is great and simple, there is no need to explain it here, for it is that simple, works on CLI versions of the OS as well
to get it type
sudo apt-get install lokkit
If you want a more comprehensive firewall download guarddog. I personally haven't used it so I cannot describe how to set it up.
to get it type
sudo apt-get install guarddog
more to come later |