Step-by-Step Comprehensive Detailed Explanation:
* Command Explanation:
* The dig command queries DNS servers. If NXDOMAIN is received, the system cannot resolve the domain. The /etc/resolv.conf file contains the DNS server configuration.
* Why Other Options are Incorrect:
* B: /etc/hosts maps IP addresses to hostnames but is not queried unless configured in /etc/nsswitch.
conf.
* C: /etc/sysconfig/network-scripts contains network interface configurations, unrelated to DNS.
* D: /etc/nsswitch.conf defines the order of name resolution methods, but it does not directly resolve domain names.
* References:
* CompTIA Linux+ Study Guide: Network Configuration
* man dig