Port Recovery

HPE Aruba Switch Port stuck disabled by UDLD: How to Fix

Q: Where can I find the HPE Aruba official documentation?

https://community.arubanetworks.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	HPE Aruba
Operating system	ArubaOS-CX
Category	Port Recovery
Skill level	Intermediate to advanced
DIY-able?	Yes with CLI access; some scenarios need Aruba TAC + RMA.

What this guide covers

Resolve a HPE Aruba switch port UDLD.

Cause + fix

Unidirectional link detected: usually a fibre cable or SFP fault. Replace one end.

CLI / commands

show interface brief
show interface 1/1/1

# Apply the fix above, then bounce the port:
configure terminal
# (interface shutdown / no shutdown, vendor-specific)
write memory

Avoid recurrence

Identify and remove the source of the violation (BPDU, MAC, storm).
Tune the protection threshold if it's too aggressive for normal traffic.
Add monitoring for repeat events.

Frequently asked questions

Will this work on my specific ArubaOS-CX version?

The procedure reflects current ArubaOS-CX behaviour. Older releases may need minor syntax adjustments. use the CLI help (? or tab-completion) to verify.

Should I open a Aruba TAC 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 HPE Aruba official documentation?

https://community.arubanetworks.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 HPE Aruba fix guides → /hpe/
All vendor guides → /vendors/

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

References

HPE Aruba support portal: https://www.arubanetworks.com/support-services/
HPE Aruba knowledge base: https://community.arubanetworks.com/
HPE Aruba security advisories: https://www.arubanetworks.com/support-services/security-bulletins/
Open a case: https://asp.arubanetworks.com/

Reference material, not professional advice. Validate against your specific ArubaOS-CX version and test in a non-production environment before applying.

What changed recently?

Fault diagnosis on a HPE 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 HPE 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.

Quick verification

Before you walk away from a HPE 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.

When to call HPE 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.