Nokia 7250 IXR-S: How to recover from a corrupted image during 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. |
Image upgrades on Nokia platforms have one cardinal rule: verify the running image first. `show version` on SR OS / SR Linux is the single most useful command in a change window because it tells you exactly what you are rolling back to if something breaks.
Across the 7250 IXR-R6 family the upgrade syntax is `file copy cf3:/timos-21.10.R1.tim cf3:/timos.tim`: pay attention to the activation step because SR OS / SR Linux treats download and activate as separate transactions. Forgetting the activation step is the single most common reason an 'upgrade' silently does nothing.
Nokia Customer Care expects you to capture pre-upgrade state and have a console session open during the change window. Anything less is a support-case waste of time if it goes sideways.
What this guide covers
Recover from a corrupted image during upgrade on a Nokia 7250 IXR-S (SR OS / SR Linux).
Step-by-step
- If at the boot loader, boot the prior image still on flash.
- If the active is corrupt and a standby still works (HA), force failover first.
- Re-download the image from the vendor portal.
- Verify checksum before copying to the device.
- Reinstall the new image and reboot.
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 recover from a corrupted image during upgrade
- Nokia 7250 IXR-X: How to recover from a corrupted image during upgrade
- Nokia 7705 SAR: How to recover from a corrupted image during upgrade
- Nokia 7250 IXR-R6: How to do an emergency image reload from the boot loader
- Nokia 7250 IXR-R6: How to rollback to the previous image after a failed upgrade
- Nokia 7250 IXR-R6: How to verify image integrity before activating
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.
Verification checklist
After applying the fix on your Nokia device, confirm:
- The original symptom is no longer reproducible.
- Related features (status LEDs, app sync, paired accessories) still work.
- The device responds to a soft reboot without the fault returning.
- Any error codes that were on display have cleared.
- Documentation (your service log, the brand companion app) reflects the change.
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
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.
Is it safe to apply during business hours?
If the device is in production use, apply during a scheduled maintenance window. Most procedures need 2-15 minutes of downtime. Capture pre-change state so you can roll back if needed.
Can I roll this back if something breaks?
Yes for software-level changes (firmware rollback, config rollback). Hardware changes are usually one-way. Always back up settings before starting.
What if the fix returns after a reboot?
Persistent fault returns mean either: a hardware fault (escalate), a configuration that's being overwritten by a sync source (check cloud profiles), or a regression in a recent firmware update (rollback).