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

vi /etc/sysconfig/network-scripts/ifcfg-eth0

ONBOOT = yes
NM_CONTROLLED = no
BOOTPROTO = dhcp

vi /etc/sysconfig/network [Hostname is needed to be specified for DHCP to work]

NETWORKING = yes
HOSTNAME =

vi /etc/resolv.conf [Optional]

search [ex: lab1.mycompany.com finance.mycompany.net abc.mycmp.com]
nameserver

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

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

Comments

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