NetworkManager connection missing after reboot – RHEL 8 Post 005

📖 ~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

Host comes up without expected IP, causing service downtime and remote access loss.

Environment & Reproduction

RHEL 8 server with static profile; reboot and run `nmcli con show –active`.

Root Cause Analysis

Connection profile not set to autoconnect, interface rename occurred, or profile bound to old device name.

Quick Triage

Confirm `NetworkManager` is active with `systemctl status NetworkManager` and inspect active profiles.

Step-by-Step Diagnosis

Use `nmcli device status`, `nmcli con show`, and check `/etc/NetworkManager/system-connections/` for profile mismatch.

Solution – Primary Fix

Set `connection.autoconnect yes`, bind profile to correct interface, reload with `nmcli con reload`, and reconnect profile.

Solution – Alternative Approaches

Use `nmtui` for profile repair or define predictable interface names consistently via provisioning templates.

Verification & Acceptance Criteria

After reboot, expected interface is up with correct IP and default route, and dependent services start cleanly.

Rollback Plan

Restore prior connection file from backup and restart NetworkManager if new profile introduces routing regression.

Prevention & Hardening

Track interface naming changes, enforce profile checks in CI images, and monitor post-boot network readiness.

Related Errors & Cross-Refs

`device not managed`, `No suitable device found`, and missing routes after startup.

Related tutorial: View the step-by-step tutorial for rhel-8.

View all rhel-8 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

`nmcli(1)`, RHEL networking documentation, and NetworkManager profile best practices.