Ubuntu Network Manager

Fix networking when installed from NFS/Live CD to use network manager

remove this entry from "/etc/network/interfaces" which will have been created and stop network manager working, cursor down, ctrl-k deletes line, ctrl-o save sudo nano -w /etc/network/interfaces

auto eth0 iface eth0 inet manual
 * 1) remove these two lines and save

sudo service network-manager restart
 * 1) restart network manager, should pick up and perform dhcp

If you network card isnt eth0, fix this here sudo nano -w /etc/udev/rules.d/70-presistent-net.rules
 * 1) remove everything from below the # comment block bit, save reboot.

To see current network manager settings nm-tool

Current connections nmcli con

To add additional DNS servers in Ubuntu 12.04, using dnsmasq by default, correctly;

DONT try adding to /etc/resolv.conf

DONT add anything in /etc/network/interfaces

DONT create files in /etc/resolvconf/resolv.conf.d/tail

edit /etc/dhcp/dhclient.conf and add or uncomment/change the prepend line, thus

prepend domain-name-servers 8.8.8.8, 208.67.222.222; request subnet-mask, broadcast-address, time-offset, routers,
 * 1) prepend domain-name-servers 127.0.0.1;

nm-tool output should now list those additional dns servers.

IPv4 Settings: Address:        192.168.2.200 Prefix:         24 (255.255.255.0) Gateway:        192.168.2.254

DNS:            8.8.8.8 DNS:            208.67.222.222 DNS:            192.168.2.254