RHEL 9: NetworkManager Interface Not Coming Up After Reboot

📖 ~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

Server loses network after reboot though interface works when manually started.

Environment & Reproduction

Run `nmcli device status` and `nmcli connection show` to locate disconnected profiles.

Root Cause Analysis

Verify NetworkManager packages with `rpm -q NetworkManager NetworkManager-libnm`.

Quick Triage

Inspect `systemctl status NetworkManager` and ensure it is enabled at boot.

Step-by-Step Diagnosis

Read boot-specific networking events using `journalctl -b -u NetworkManager`.

Solution – Primary Fix

Set profile autoconnect with `nmcli connection modify connection.autoconnect yes` and reconnect.

Solution – Alternative Approaches

After connectivity returns, confirm `firewalld` zone assignment matches interface role.

Verification & Acceptance Criteria

SELinux rarely blocks NetworkManager defaults, but audit if custom scripts are involved.

Rollback Plan

Reboot and verify interface is up with expected IP address without manual intervention.

Prevention & Hardening

Avoid manual edits that conflict with `nmcli` managed profiles on RHEL 9.

Related Errors & Cross-Refs

Restore prior connection profile backup in `/etc/NetworkManager/system-connections/` if needed.

Related tutorial: View the step-by-step tutorial for rhel-9.

View all rhel-9 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

Use `man nmcli` and RHEL networking docs for profile-based management.