Upgrade Failure

Nokia 7250 IXR-R6: How to rollback to the previous image after a failed 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.

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-R6 (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.

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.

Common patterns we see

When this symptom shows up on a Nokia device, three patterns repeat:

1. Recent firmware update changed behavior, the symptom started within a week of an OTA push. Rollback or wait for the hotfix. 2. Environmental trigger. temperature, humidity, line voltage, network changes. Look at what changed in the environment. 3. Cumulative wear, components like batteries, gaskets, fans degrade over time. Replace the consumable rather than chasing a software fix.

Knowing which pattern applies saves time on the wrong fix.

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.

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.