🟠 High   ⏱ 5–30 min  Last verified: 19 May 2026
Affected versions: SUSE Linux Enterprise Server 16

📖 ~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

`transactional-update` ends success, but `snapper status` shows no new default after reboot.

Environment & Reproduction

Happens on systems where the boot loader entry was not refreshed by the tukit hook.

Root Cause Analysis

`tukit reboot` was skipped or interrupted, leaving the new snapshot non-default.

Quick Triage

Verify the pending snapshot: `snapper –no-headers list | grep ‘+’`.

Step-by-Step Diagnosis

Run `transactional-update –dry-run` to confirm pending state, then check `/etc/grub.d/`.

Illustrative mockup for sles-16 — tukit_reboot-fail_terminal
Terminal diagnostics for Transactional update completes but reboot does not switch snapshot — Illustrative mockup — Progressive Robot

Solution – Primary Fix

Re-execute `transactional-update apply` followed by `systemctl reboot`.

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Illustrative mockup for sles-16 — tukit_reboot-fail_logs
Logs and evidence for Transactional update completes but reboot does not switch snapshot — Illustrative mockup — Progressive Robot

Solution – Alternative Approaches

Use `tukit close` and a manual snapshot-set-default cycle if tukit hangs.

Verification & Acceptance Criteria

After reboot `snapper status` lists the new snapshot as default and read-write.

Rollback Plan

Roll back via `transactional-update rollback last` if the new snapshot breaks services.

Prevention & Hardening

Wrap transactional-update runs in a CI smoke-test before fleet rollout.

Pairs with `grub2-mkconfig` warnings when boot env is stale.

Related tutorial: View the step-by-step tutorial for sles-16.

View all sles-16 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

transactional-update and tukit manuals.

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