/etc/resolv.conf

Purpose

The file /etc/resolv.conf provides a list of servers used for handling DNS requests, to resolve names to IP addresses, and reversed.

Depending on your Linux system, the /etc/resolv.conf might be a symbolic link pointing to a so-called stub of systemd that handles DNS requests via systemd-resolved. Otherwise, it is a regular file and contains the DNS servers and some optional configuration settings, such as time-outs.

File permissions

Usually the /etc/resolv.conf file will have the permissions of 644 (rw-r--r--), meaning owner can read and write, group and others can read.

More information and usage of /etc/resolv.conf

The following articles have a reference to /etc/resolv.conf and might be worth reading to learn more.

• Audit security events on Unix systems
• List network interfaces on Linux
• Networking
• How to see which DNS server is used
• Linux DNS Tuning for Performance and Resilience
• Linux Security Guide for Hardening IPv6