Nokia 7250 IXR-S: How to rollback to the previous image after a failed upgrade
By Sai Kiran Pandrala · reviewed by Sai Kiran Pandrala, Editor Last verified: 2026-05-30
| Vendor | Nokia |
|---|---|
| Operating system | SR OS / SR Linux |
| Category | Upgrade Failure |
| Skill level | Intermediate to advanced |
| DIY-able? | Yes with CLI access; some scenarios need Nokia Customer Care + RMA. |
On Nokia kit the upgrade ritual matters more than the speed. `show version` first, `admin tech-support` second, then the actual `file copy cf3:/timos-21.10.R1.tim cf3:/timos.tim`, that order on SR OS / SR Linux saves the most support-case time when something goes wrong on the 7250 IXR-R6 unit.
Integrity verification is non-negotiable. Vendor mirrors get corrupted, internal staging servers serve stale files, and the checksum step on SR OS / SR Linux is the only thing standing between you and a chassis that boots to a recovery prompt.
What follows is the safe-rollback variant. If you need an in-place upgrade with zero rollback path, this guide is not it. and frankly that is not a thing you should be doing on production gear.
What this guide covers
Rollback to the previous image after a failed upgrade on a Nokia 7250 IXR-S (SR OS / SR Linux).
Step-by-step
- Confirm there's a previous image still on flash.
- Set the boot variable to that previous image.
- Reboot.
- Verify the version is back to the prior release.
- Investigate the upgrade failure separately, do not re-attempt without root cause.
CLI / commands
# Boot recovery prompt: BOF> (Boot Options File)
# Verify image
show version
# Upgrade
file copy cf3:/timos-21.10.R1.tim cf3:/timos.tim
# Save / commit
admin save
# Rollback
rollback
Recovery options
- Boot loader recovery (BOF> (Boot Options File))
- Rollback to the previous image with
rollback - Force failover to a known-good standby (HA platforms)
Frequently asked questions
Will this work on my specific SR OS / SR Linux version?
The procedure reflects current SR OS / SR Linux behaviour. Older releases may need minor syntax adjustments: use the CLI help (? or tab-completion) to verify.
Should I open a Nokia Customer Care case immediately?
Open one if you suspect hardware failure or the symptom persists after a maintenance-window reload. Make sure your support entitlement is active first.
Where can I find the Nokia official documentation?
https://documentation.nokia.com, search the product family + feature name.
Is this procedure safe in production?
Test in a lab or maintenance window first. Capture pre-change state so you can roll back.
Related guides
Related fixes
Related guides worth a look while you sort this one out:
- Nokia 7250 IXR-R6: How to rollback to the previous image after a failed upgrade
- Nokia 7250 IXR-X: How to rollback to the previous image after a failed upgrade
- Nokia 7705 SAR: How to rollback to the previous image after a failed upgrade
- Nokia 7250 IXR-R6: How to do an emergency image reload from the boot loader
- Nokia 7250 IXR-R6: How to perform a controlled upgrade with rollback safety net
- Nokia 7250 IXR-R6: How to recover from a corrupted image during upgrade
References
- Nokia support portal: https://customer.nokia.com
- Nokia knowledge base: https://documentation.nokia.com
- Nokia security advisories: https://www.nokia.com/about-us/security/vulnerability-management/
- Open a case: https://customer.nokia.com
Reference material, not professional advice. Validate against your specific SR OS / SR Linux version and test in a non-production environment before applying.
What changed recently?
Fault diagnosis on a Nokia device goes faster when you map the symptom to a recent change:
- Did firmware update in the last 7 days?
- Did the network (router, ISP, VPN) change?
- Was the device moved physically?
- Did paired devices (phone, hub, app) update?
- Were any accessories swapped in or out?
The answer narrows the root cause to a manageable subset.
Safety + preconditions
Before any work on a Nokia device:
- Unplug from mains for any internal-access procedure.
- Discharge stored energy (capacitors in PSUs, residual battery charge) per manufacturer guidance.
- Use ESD-safe handling for boards and modules. no carpet, no wool sleeves.
- Avoid moisture; never apply liquids near vents or connectors.
- If you smell smoke, see scorch marks, or feel uneven heat, stop and escalate.
How to confirm it's actually fixed
On a Nokia device, the test is rarely "reboot and see". Use this list:
- Active reproduction: trigger the original failure path on purpose.
- Indirect reproduction: do an activity that would expose the same subsystem.
- Status indicator review: every LED / display / app status should be green.
- 24-hour soak: leave the device under normal load overnight; check the next morning.
- Telemetry check: review the device or app's diagnostic log for new error entries.
When to call Nokia support instead
Escalate if:
- The same symptom returns within 24 hours of a clean fix.
- You see physical damage (burn marks, swollen battery, cracked PCB).
- The device is in warranty and a hardware replacement is the cheaper outcome.
- Repair requires specialised tools you don't own (alignment jigs, calibration software).
- Following the official path keeps the warranty intact, which matters more than the time spent.
More frequently asked questions
What if my model isn't exactly the same revision?
Cross-check the model code on the rating plate against the manufacturer support page. Major firmware generations sometimes shift the menu path; the option is usually under a similarly-named section.
Will the procedure work on the international variant?
Some features and firmware paths are region-locked. Check the model spec sheet to confirm your variant supports the menu option referenced. If you're outside the US/EU, look for the regional support portal.
How often should I run preventive checks?
Quarterly for most consumer devices; monthly for production / commercial devices. Set a calendar reminder so the device stays healthy between issues.
Why is this happening on a brand-new unit?
Out-of-box defects do occur. If you've owned the device under 30 days and the symptom persists after a factory reset, escalate to the seller for replacement under DOA terms before opening a manufacturer support case.
Does this affect other devices on my network?
Generally no. The procedure is local to this device. Network-side changes (firmware updates that affect TLS, SMB, or routing) are flagged explicitly in the steps.