RHEL 7 Network Service Restart Breaks Static Route

📖 ~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

Inter-subnet traffic fails after service network restart, cutting app tiers off from databases.

Environment & Reproduction

RHEL 7 with static routes added manually via ip route reproduces route loss on reboot or network restart.

Root Cause Analysis

Routes were not persisted in ifcfg or route-* files, so service restart flushes temporary kernel routes.

Quick Triage

Run ip route, check network service/systemctl status, inspect firewalld zones, and validate SELinux network contexts.

Step-by-Step Diagnosis

Compare runtime route table to config files and review journalctl logs around network restart timing.

Solution – Primary Fix

Add persistent route entries in /etc/sysconfig/network-scripts/route-* and restart network service safely.

Solution – Alternative Approaches

Use NetworkManager nmcli persistent routes, static routing daemon, or automation-driven interface templates.

Verification & Acceptance Criteria

Route survives reboot and service restart, and traceroute confirms correct path to dependent networks.

Rollback Plan

Remove new route file entries, restore prior scripts, and restart service to return to baseline routing.

Prevention & Hardening

Codify routes in infrastructure code, test restart scenarios, and monitor for route-table drift.

Related Errors & Cross-Refs

Related to DNS resolver fallback failure, firewalld forwarding disablement, and systemctl ordering issues at boot.

Related tutorial: View the step-by-step tutorial for rhel-7.

View all rhel-7 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

Read RHEL 7 network-scripts docs, service/network migration notes, and journalctl networking debug guidance.