Upgrade Failure

Nokia 7250 IXR-R6: How to recover from a corrupted image during upgrade

Q: Where can I find the Nokia official documentation?

https://documentation.nokia.com — search the product family + feature name.

By Sai Kiran Pandrala · reviewed by Sai Kiran Pandrala, Editor Last verified: 2026-05-30

⚡ At a glance

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.

I have run more Nokia upgrades than I can count and the only ones that hurt are the ones where I skipped image-integrity verification. SR OS / SR Linux either ships a `verify` step or expects you to checksum the file before file copy cf3:/timos-21.10.R1.tim cf3:/timos.tim.

On the 7250 IXR-R6 platform the activation phase is where you lose data-plane connectivity. Plan the change window around that window, not the full upgrade duration.

If something goes wrong, the rollback path on SR OS / SR Linux is well-trodden. but only if you saved running-config before starting. Do that now, before anything else.

What this guide covers

Recover from a corrupted image during upgrade on a Nokia 7250 IXR-R6 (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.

All Nokia fix guides → /nokia/
All vendor guides → /vendors/

Related guides worth a look while you sort this one out:

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.

Why this matters for your day-to-day

A Nokia device that's misbehaving costs more than the fix itself: lost productivity, missed calls, security risk, even safety risk in some categories. Treating the symptom quickly with a documented procedure is cheaper than letting it persist. The steps above are written to get you back to working in under an hour where possible, and to flag clearly when escalation is the right call.

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.

Quick verification

Before you walk away from a Nokia device fix, run through:

1. Reproduce the original trigger. does the issue reappear? 2. Check the device's status / health screen for any new alerts. 3. Confirm paired devices (app, hub, controller) reconnected. 4. Save / commit any configuration changes per the device's normal workflow. 5. Note the change in your maintenance log with date + firmware version.

Escalation guide

For a Nokia device, the right escalation depends on impact:

Cosmetic / minor: log a ticket via the Nokia app or web portal. Response 1-3 business days.
Mid-impact: phone support. Have your serial number ready.
Critical (production down, safety issue): in-person dealer / TAC visit. Bring proof of purchase.
Out of warranty: third-party repair shop with manufacturer-certified technicians.