I am trying to block a few websites on a lucid lynx, I tried editing /etc/hosts and that blocks access via url but the site still open if I enter the ip on the browser, how can I block ip access also? (without using any extra software besides what linux 10.04 have by default)
You can block the website's IP using an iptables rule. Something along the flavor provided below.
Just replace the zeros with the IP of the website you wish to deny access to. This syntax also supports a wildcard. By typing an IP with a zero in it, you are effectively blocking the entire span of that field. For example, 192.168.13.0 references the IP range of 192.168.13.1 to 192.168.13.254.
In addition to blocking by IP, you can also block by hostname using this same syntax. Just change the IP address to the domain name and it'll do the rest of the work for you.
So you can do all of what you wanted in iptables (freeing up your hosts file from needless records).