What file translates hostnames or domain names to IP addresses?

The file that translates hostnames or domain names to IP addresses is the /etc/hosts file. This file is a simple text file used for local hostname resolution. It allows the system to map a hostname to an IP address without the need to query a DNS server. When you attempt to access a hostname, the system looks in the /etc/hosts file first before checking any DNS settings.

This functionality is essential for network communication, as it allows local resolution of names to addresses, facilitating the ability to access other systems and services using human-readable names instead of numeric IP addresses. The format of entries in the /etc/hosts file typically includes the IP address followed by the associated hostname(s), and it can include comments for clarity.

Other options, while related to system and network configuration, do not perform hostname to IP address translation: /etc/sysconfig/network pertains to network interface configuration, /proc contains kernel and process information, and /sys represents a virtual filesystem that abstracts hardware devices.