Hardware Failure

Nokia 7705 SAR POST failure on startup: Diagnose & Fix

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	Hardware Failure
Skill level	Intermediate to advanced
DIY-able?	Yes with CLI access; some scenarios need Nokia Customer Care + RMA.

A Nokia platform behaving badly is usually one of three things: a thermal/PSU issue caught by `show chassis environment`, a transceiver problem caught by `show port 1/1/1`, or a boot-loader hang you only see on the console. SR OS / SR Linux surfaces all three differently from competitors, so the diagnostic order matters.

I will be honest: on the 7705 SAR family I have seen at least one false-positive from the on-box monitoring per quarter. Always cross-check what `show version` and `show chassis environment` reports against the physical front-panel and a smell test of the chassis.

If this is your first Nokia hardware issue, the good news is that Nokia Customer Care is competent and the part-replacement RMA cycle is usually under a week for a covered unit.

What this guide covers

Diagnose and recover from POST failure on startup on a Nokia 7705 SAR.

Step-by-step

Note the exact POST failure code from the console.
Look up the code in the vendor hardware install guide.
Common: memory test fail (RMA RAM / motherboard), FPGA fail (RMA mainboard).
Open a Nokia Customer Care case with the POST log and the device serial.

CLI / commands

# Verify hardware state
show version
show chassis
show chassis environment

# Collect for Nokia Customer Care
admin tech-support

When to RMA

Repeated failure after re-seat and power-cycle
Visible burn, scorching, or physical damage
POST or memory diagnostic failure
Hardware crashinfo without a software workaround

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.

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.

Before you start

A few things to confirm so the Nokia device fix goes cleanly:

Latest firmware downloaded if you're going to update.
Warranty + support contract status checked, opening sealed parts may void it.
Backup of current configuration (where applicable) taken.
Spare parts on hand if you anticipate replacement.
Adequate workspace, lighting, and time: rushing causes regressions.

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.