Network Configuration

Reference:

https://help.ubuntu.com/12.04/serverguide/network-configuration.html

http://manpages.ubuntu.com/manpages/hardy/man5/interfaces.5.html

Check network card name and status, even not configured

#ip a

NIC configuration scripts

Redhat / CentOS: /etc/sysconfig/network-scripts

Ubuntu: /etc/network

Start network

#service network start

DNS resolver

Redhat / CentOS : /etc/resolv.conf

Ubuntu: /etc/network/interfaces, such as

auto eth0

iface eth0 inet static     address 192.168.3.3     netmask 255.255.255.0     gateway 192.168.3.1     dns-search example.com sales.example.com dev.example.com     dns-nameservers 192.168.3.45 192.168.8.10

This article explains where DNS setup goes in ubuntu.

http://www.stgraber.org/2012/02/24/dns-in-ubuntu-12-04/

On server which do not use network manager, dns usually goes to /etc/network/interfaces. However, without down/up the interface or restart server, it will not take effect. Use resolvconf to manually add the config, see:

http://askubuntu.com/questions/224966/how-do-i-get-resolvconf-to-regenerate-resolv-conf-after-i-change-etc-network-in