Ubuntu 20.04 LTS NIC Driver Not Loaded After Kernel Update

📖 ~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

Network interface disappears after reboot, severing remote connectivity and service reachability.

Environment & Reproduction

Seen after kernel upgrades where out-of-tree modules or firmware packages are mismatched.

Root Cause Analysis

Required kernel module fails to build or load because ABI or firmware dependencies changed.

Quick Triage

Check loaded modules, dmesg output, and firmware presence for the affected NIC model.

Step-by-Step Diagnosis

Inspect module build logs and kernel compatibility to confirm missing driver load path.

Solution – Primary Fix

Install matching driver and firmware packages, rebuild modules, and persist correct load configuration.

Solution – Alternative Approaches

Boot prior kernel version or use supported in-tree driver where hardware permits.

Verification & Acceptance Criteria

NIC appears reliably across reboots with stable link and packet flow metrics.

Rollback Plan

Revert to previous kernel and module set if updated driver stack is unstable.

Prevention & Hardening

Validate driver compatibility pre-upgrade and maintain tested fallback kernel entries.

Related Errors & Cross-Refs

Connected to DKMS failures and missing firmware blob warnings in boot logs.

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

Use Ubuntu kernel, DKMS, and hardware enablement documentation for driver lifecycle guidance.