Configure DNS Linux¶

Introduction¶

This guide focuses on configure dns linux from an administrator's terminal. The goal is to configure or verify networking without guessing which layer is broken.

When You Need This¶

Use this workflow when a host cannot reach another system, name resolution fails, a route is missing, a port is blocked, or NetworkManager configuration needs to be persistent.

Key Files and Commands¶

resolvectl status
cat /etc/resolv.conf
dig cloudarks.com
getent hosts cloudarks.com

Important areas to check are resolver files, NetworkManager DNS settings, search domains, and upstream reachability. On RHEL-style systems, NetworkManager and firewalld are usually part of the answer.

Step-by-Step Configuration¶

Start by viewing live state, then change the persistent connection profile if needed. For NetworkManager-managed systems, prefer persistent profiles over runtime-only changes.

resolvectl status
cat /etc/resolv.conf
dig cloudarks.com

Verification¶

getent hosts cloudarks.com
nmcli device show

A healthy result should look similar to:

cloudarks.com. 300 IN A 203.0.113.20
203.0.113.20 cloudarks.com

Troubleshooting¶

Check interface state, IP address, default route, DNS server, firewall zone, and listening process. If a connection works by IP but not by name, focus on DNS. If DNS works but traffic fails, focus on routes, firewall, and service binding.

Common Mistakes¶

• Making several changes at once, which hides the real cause.
• Skipping logs or verification commands after a change.
• Assuming the problem is fixed because one command returned successfully.

Quick Checklist¶

• Confirm link state and IP address.
• Confirm default gateway and specific routes.
• Confirm DNS separately from IP connectivity.
• Check listening sockets and firewall zones.
• Make persistent changes through NetworkManager when appropriate.

Related Guides¶

• IP Command Networking Guide
• ss Command Networking Guide
• Configure firewalld Linux
• Troubleshoot DNS Linux

Summary¶

Good Linux networking work separates address, route, DNS, firewall, and service checks. Verify each layer before moving to the next one.