Ubuntu 20.04 Wi-Fi disconnects or fails to reconnect

📖 ~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

On Ubuntu 20.04, Wi-Fi may drop unexpectedly or fail to reconnect after sleep.

Environment & Reproduction

The adapter appears connected, but internet access is intermittent or unavailable.

Root Cause Analysis

Likely causes include unstable driver power saving, weak signal, or NetworkManager state issues.

Quick Triage

Toggle Wi-Fi off and on, confirm the correct SSID, and test another network if possible.

Step-by-Step Diagnosis

Run nmcli device status, rfkill list, ip a, and journalctl -u NetworkManager –since -30m.

Solution – Primary Fix

Restart NetworkManager, forget and re-add the network profile, then disable unstable power-saving options.

Solution – Alternative Approaches

Update linux-firmware, test a different channel band, and retry reconnect after suspend cycles.

Verification & Acceptance Criteria

Connection remains stable for normal browsing, updates, and resume from sleep.

Rollback Plan

Revert wireless config changes and restore previous known-good NetworkManager settings.

Prevention & Hardening

Use updated router firmware and avoid aggressive Wi-Fi power management on flaky adapters.

Related Errors & Cross-Refs

See issues involving DNS failures, suspend resume networking, and adapter driver regressions.

Related tutorial: View the step-by-step tutorial for Ubuntu 20.04 LTS.

View all Ubuntu 20.04 LTS tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

Consult nmcli and NetworkManager documentation for Ubuntu 20.04 networking troubleshooting.