Sophos XGS 116 power supply failed: Diagnose & Fix
By Sai Kiran Pandrala · reviewed by Sai Kiran Pandrala, Editor Last verified: 2026-05-30
| Vendor | Sophos |
|---|---|
| Operating system | SFOS (Sophos Firewall OS) |
| Category | Hardware Failure |
| Skill level | Intermediate to advanced |
| DIY-able? | Yes with CLI access; some scenarios need Sophos Support + RMA. |
A Sophos platform behaving badly is usually one of three things: a thermal/PSU issue caught by `system diagnostics show device-info`, a transceiver problem caught by `system interface show name=Port1`, or a boot-loader hang you only see on the console. SFOS (Sophos Firewall OS) surfaces all three differently from competitors, so the diagnostic order matters.
I will be honest: on the XGS 87 family I have seen at least one false-positive from the on-box monitoring per quarter. Always cross-check what `system version (CLI)` and `system diagnostics show device-info` reports against the physical front-panel and a smell test of the chassis.
If this is your first Sophos hardware issue, the good news is that Sophos Support 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 power supply failed on a Sophos XGS 116.
Step-by-step
- Confirm which PSU failed.
- Verify the remaining PSU has enough capacity for the device + line cards + PoE budget.
- Note the failed PSU's part number.
- Replace during a maintenance window, most enterprise PSUs are hot-swappable.
- After replacement, confirm both PSUs show OK.
CLI / commands
# Verify hardware state
system version (CLI)
system status
system diagnostics show device-info
# Collect for Sophos Support
system support-tools generate-debug-info
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 SFOS (Sophos Firewall OS) version?
The procedure reflects current SFOS (Sophos Firewall OS) behaviour. Older releases may need minor syntax adjustments. use the CLI help (? or tab-completion) to verify.
Should I open a Sophos Support 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 Sophos official documentation?
https://support.sophos.com/support/s/, 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:
- Sophos XGS 107 power supply failed: Diagnose & Fix
- Sophos XGS 126 power supply failed: Diagnose & Fix
- Sophos XGS 87 power supply failed: Diagnose & Fix
- Sophos AP6 420 power supply failed: Diagnose & Fix
- Sophos AP6 420E power supply failed: Diagnose & Fix
- Sophos XGS 116 fan tray failed: Diagnose & Fix
References
- Sophos support portal: https://support.sophos.com
- Sophos knowledge base: https://support.sophos.com/support/s/
- Sophos security advisories: https://www.sophos.com/en-us/security-advisories
- Open a case: https://secure2.sophos.com/en-us/support.aspx
Reference material, not professional advice. Validate against your specific SFOS (Sophos Firewall OS) version and test in a non-production environment before applying.
What changed recently?
Fault diagnosis on a Sophos 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 Sophos 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.
How to confirm it's actually fixed
On a Sophos 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 Sophos 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 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).
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.
Will this void my warranty?
Applying official firmware updates and following the user manual will not affect warranty. Opening sealed components, jumping safety circuits, or using third-party parts can void warranty in most jurisdictions.
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.
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.