FreeBSD 15: NFS stale file handle after snapshot rollback

📖 ~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

Applications lose access to mounted paths and read/write operations fail with stale handle errors.

Environment & Reproduction

Common after ZFS snapshot rollback, dataset reparenting, or rapid export map changes.

Root Cause Analysis

Client-side file handles reference inode and export state that no longer matches server objects.

Quick Triage

Identify impacted exports and clients, then assess whether namespace rollback changed object identity.

Step-by-Step Diagnosis

Correlate server export state, dataset history, and client mount metadata to confirm handle invalidation.

Solution – Primary Fix

Refresh exports and remount clients in sequence after namespace consistency is restored.

Solution – Alternative Approaches

Serve immutable rollback snapshots under separate export paths to avoid handle reuse.

Verification & Acceptance Criteria

All clients remount successfully and application IO resumes without stale handle recurrence.

Rollback Plan

Revert export changes and restore previous snapshot presentation strategy if remount fails.

Prevention & Hardening

Apply controlled export versioning and maintenance windows for namespace-changing storage actions.

Related Errors & Cross-Refs

Connected to ZFS clone promotions, failover remount races, and inconsistent automounter maps.

Related tutorial: View the step-by-step tutorial for freebsd-15.

View all freebsd-15 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

nfsd and mount_nfs man pages plus FreeBSD NFS administration guidance.