CentOS Stream 9 – Common Problem 240 – Diagnosis and Fix

📖 ~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

Local disk appears as multipath device

Environment & Reproduction

Default CS9 multipath config does not blacklist local SATA disks.

Root Cause Analysis

multipathd claims local device because WWID is not blacklisted.

Quick Triage

multipath -ll and lsblk output show extra dm-X for local disk.

Step-by-Step Diagnosis

Run: multipath -ll; cat /etc/multipath/wwids; udevadm info /dev/.

Solution – Primary Fix

Edit /etc/multipath.conf blacklist section adding wwid and run multipath -F; multipath -r.

Solution – Alternative Approaches

Use find_multipaths strict mode to require explicit allowlist.

Verification & Acceptance Criteria

multipath -ll lists only SAN devices and lsblk shows expected layout.

Rollback Plan

Restore /etc/multipath.conf backup and reload multipathd.

Prevention & Hardening

Bake multipath.conf into kickstart per hardware profile.

Related Errors & Cross-Refs

Pairs with duplicate UUID warnings and unexpected dm device names.

Related tutorial: View the step-by-step tutorial for centos-stream-9.

View all centos-stream-9 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

multipath.conf(5) and multipathd(8).