What is the purpose of the 'hosts' file in Linux?

The purpose of the 'hosts' file in Linux is to map hostnames to IP addresses locally. This file serves as a local DNS resolver that allows a system to resolve hostnames without needing to query a DNS server. When an application attempts to connect to a hostname, the system first checks the 'hosts' file to see if there is a corresponding IP address defined. If a match is found, the system uses that address, speeding up the resolution process and sometimes allowing access to local or private network resources without external DNS queries.

This local mapping is particularly useful in scenarios where a DNS server may not be available, or when you want to override a DNS entry for testing or development purposes. The format of the 'hosts' file typically consists of lines with an IP address followed by one or more associated hostnames.

Other options, such as storing system logs, configuring network interfaces, or managing routing tables, relate to different aspects of network and system management. These tasks are handled by different mechanisms and files within the Linux operating system, making them distinct from the primary function of the 'hosts' file.