In which file is DNS information referenced?

The file that typically contains DNS information in a Unix-based operating system is named resolv.conf. This file is primarily used by the system to define the DNS servers that the host should query when resolving domain names into IP addresses. The entries in resolv.conf include the addresses of the DNS servers (usually referred to as nameservers) and can also include search domains that the resolver can append to unqualified domain names.

In contrast, other options have distinct roles:

• The /etc/network/interfaces file is primarily used to configure network interfaces on Debian-based systems and does not store DNS information.

• The hosts file is utilized for local hostname resolution. It allows the mapping of hostnames to IP addresses without querying a DNS server, but it does not serve as a centralized reference for DNS information.

• The dns.conf file is not a standard configuration file found in typical Unix-based systems, making it less relevant in this context for referencing DNS information.

Thus, resolv.conf is indeed the correct answer, serving as the crucial file for specifying DNS server addresses needed for name resolution.