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Configuring Network on Centos 6 Minimal Installation

When a system is installed with CentOS 6 minimal version, it's network is not configured initially and has to be manually taken care of. There are two ways of going about this:

DHCP
  1.  vi /etc/sysconfig/network-scripts/ifcfg-eth0
    • ONBOOT = yes
    • NM_CONTROLLED = no
    • BOOTPROTO = dhcp
  2.  vi /etc/sysconfig/network [Hostname is needed to be specified for DHCP to work]
    • NETWORKING = yes
    • HOSTNAME =
  3.  vi /etc/resolv.conf [Optional]
    • search [ex: lab1.mycompany.com finance.mycompany.net  abc.mycmp.com]
    • nameserver
  4. Once all the above steps are done, restart the networking service:
    • /etc/init.d/network restart
[For troubleshooting]
You can also consider using "dhclient eth0" to obtain an ip address for eth0 from dhcp server.

Static IP Address
  1. vi /etc/sysconfig/network-scripts/ifcfg-eth0
    • ONBOOT = yes
    • NM_CONTROLLED = no
    • BOOTPROTO = none
    • IPADDR =
    • NETMASK = [for a /24 network it will be 255.255.255.0]
    • GATEWAY = [Optional]
    •  USERCTL = yes/no [Optional] (yes - allows non-root users to control this device)

Additional configuration parameters are defined in the CentOS documentation
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