use ping from terminal to test your connection
make sure you ping an ip address. if u can ping successfully,
but can't access web site from the browser (for example u get unknown host),
probably the dns is not working. If it is so then follow these steps,
Setting up Name to Address Resolution (DNS)
1) get your isp's nameserver ip address from your isp. Optionally get it from http://www.dnsreport.com
by inputing your isp's domain name.
2) login as root and edit the file /etc/resolv.conf, use the command: vi /etc/resolv.conf
the content should be like this:
the permission of the file should be like this:
--rw-r--r-- 1 root root 13 Feb 19 01:46 /etc/resolv.conf
3) vi the file /etc/host.conf
the content should be like this
order hosts, bind
4) Good luck!!