The important Linux network configuration files are explained below:
The main purpose of /etc/hosts configuration file is to resolve hostnames that cannot be resolved any other way. It can also be used to resolve hostnames on small networks with no DNS server. Regardless of the type of network the computer is on, this file should contain a line specifying the IP address of the loopback device (127.0.0.1) as localhost.localdomain.
The /etc/resolv.conf configuration file specifies the IP addresses of DNS servers and the search domain. Unless configured to do otherwise, the network initialization scripts populate this file.
The /etc/sysconfig/network configuration file specifies routing and host information for all network interfaces.