Oracle Linux 10 – nmstate apply fails because route metric values are invalid – Fix & Prevention

📖 ~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

nmstatectl apply fails and network desired-state automation halts.

Environment & Reproduction

Invalid route metric ranges or duplicate defaults in YAML state definition.

nmstatectl apply /tmp/state.yml

Root Cause Analysis

Schema validation catches unsupported metric values and route conflicts.

Quick Triage

Capture failing state and active routes from kernel/NM.

nmstatectl show
ip route
systemctl status NetworkManager
firewall-cmd --state
journalctl -u NetworkManager -n 60 --no-pager

Step-by-Step Diagnosis

Validate YAML and compare desired routes with active default gateways.

python -m yaml /tmp/state.yml || true
nmstatectl gc /tmp/state.yml
ip -4 route show table main

Solution – Primary Fix

Correct route metrics and remove duplicate default entries before apply.

sed -i 's/metric: 0/metric: 100/' /tmp/state.yml
nmstatectl apply /tmp/state.yml
systemctl restart NetworkManager

Solution – Alternative Approaches

Apply incremental route changes via nmcli when nmstate transactions are too broad.

nmcli connection modify eth0 ipv4.route-metric 100
nmcli connection up eth0

Verification & Acceptance Criteria

State apply returns success and effective route table matches policy.

nmstatectl show
ip route

Rollback Plan

Reapply previous known-good state file.

nmstatectl apply /root/backup/state-good.yml

Prevention & Hardening

Lint nmstate definitions in CI before rollout.

nmstatectl gc /tmp/state.yml

Related Errors & Cross-Refs

Related to DHCP/static overlap and policy routing table precedence issues.

Related tutorial: View the step-by-step tutorial for oracle-linux-10.

View all oracle-linux-10 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

nmstate schema and RHEL network automation documentation.