I tweaked my system by installing ftp server and a dns server. I think in the process I messed up resolv.conf and the hosts file.
Now I want to restore it but am not able to do so.
I am using ubuntu 14.04 x86_64.
Here is a screenshot that might help:
If you are running a currently-supported desktop version of Ubuntu, then networking should be handled by the NetworkManager service, and your /etc/network/interfaces file should contain only the default loopback interface definition
auto lo
iface lo inet loopback
To fix your /etc/resolv.conf file, you probably need to reconfigure the package from the command line using
sudo dpkg-reconfigure resolvconf
It will present you with a question about preparing /etc/resolv.conf for dynamic updates - answer "Yes". It may also present you with another question about temporarily appending your existing config to the dynamic one - if so you should probably answer "No" to that one. This will re-create the default symbolic link in place of your manually-edited file.
