Good day to you!
Configuring network in CentOS is very simple. You need to edit one file and restart the network utility. But first things first.
In CentOS, network settings are located:
/etc/sysconfig/network-scripts/
For each network card, a separate settings file is created: ifcfg-eth0, ifcfg-eth1 .... ifcfg-eth99. The name of the file for the first or the only network card will be ifcfg-eth0. To edit it, type in the console:
vi /etc/sysconfig/network-scripts/ifcfg-eth0
Press "i" button to switch to editing mode and insert one of the following configurations in the file.
Configuring the static IP network
The typical configuration is as follows:
DEVICE='eth0' //network card name
TYPE=Ethernet // network card type
BOOTPROTO=none // automatic setup protocol (for example, DHCP)
ONBOOT='yes' //switch on when starting the system
IPADDR=177.61.211.162 //Static IP
NETMASK=255.255.192.0 //Subnet mask
GATEWAY=177.61.192.1 // Default gateway
DNS1=8.8.8.8 //DNS server
DNS2=8.8.4.4
If your CentOS server operates within the local home network, you can find the subnet mask and communication server on any other PC with Windows or Linux. You can occupy any free IP address. If the server is connected to a provider or located in a data center, you should receive all the settings from your provider.
Configuring the dynamic IP network
It’s a very rare case, when the dynamic IP network is to be configured in CentOS, but I will post the settings just to be on a safe side:
DEVICE='eth0' // network card name
TYPE=Ethernet // network card type
BOOTPROTO='dhcp' // automatic setup protocol
ONBOOT='yes' // switch on when starting the system
Applying new configurations of the network
After you have made all the necessary alterations in ifcfg-eth0 file, click “Esc” button to exit editing mode and after that, type “:wq” for stateful exit from the editing program and press “Enter”.
Now, check the settings of the main configuration file:
vi /etc/sysconfig/network
There should be the following content:
NETWORKING=yes
HOSTNAME=dev.helpdesk.zone //you host name
To apply the alterations, you should restart the network interface:
/etc/init.d/network restart
If you have more questions or need details - please, ask a question or leave a comment.