CentOS Stream 10 – Common Problem 230 – Diagnosis and Fix

📖 ~1 min read

Table of contents

1. Symptom & Impact
2. Environment & Reproduction
3. Root Cause Analysis
4. Quick Triage
5. Step-by-Step Diagnosis
6. Solution – Primary Fix
7. Solution – Alternative Approaches
8. Verification & Acceptance Criteria
9. Rollback Plan
10. Prevention & Hardening
11. Related Errors & Cross-Refs
12. References & Further Reading

Symptom & Impact

DNS resolution flips between resolvers because both NM and systemd-resolved manage /etc/resolv.conf.

Environment & Reproduction

Triggered when systemd-resolved is enabled but NetworkManager dns plugin is left at the default.

Root Cause Analysis

Two managers race to populate the stub resolver, producing inconsistent or stale resolver order.

Quick Triage

Run resolvectl status and compare to nmcli device show to confirm conflicting upstream servers.

Step-by-Step Diagnosis

Run: resolvectl status; nmcli -f IP4.DNS,IP6.DNS device show; cat /etc/resolv.conf.

Solution – Primary Fix

Set NetworkManager dns=systemd-resolved and ensure /etc/resolv.conf points to 127.0.0.53.

Solution – Alternative Approaches

Disable systemd-resolved if not needed: systemctl disable –now systemd-resolved.service.

Verification & Acceptance Criteria

resolvectl status shows the correct interface DNS and queries resolve consistently.

Rollback Plan

Re-enable systemd-resolved and revert NetworkManager.conf if the stub resolver is required.

Prevention & Hardening

Choose a single DNS owner per host and document it in build standards.

Related Errors & Cross-Refs

Often paired with VPN split DNS and search domain misconfiguration.

Related tutorial: View the step-by-step tutorial for centos-stream-10.

View all centos-stream-10 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

systemd-resolved(8) and NetworkManager documentation.