Cisco IOS Error %EIGRP-5-NBRCHANGE: Causes & How to Fix
By Sai Kiran Pandrala · reviewed by Sai Kiran Pandrala, Editor Last verified: 2026-05-30
| Section | Cisco IOS Error Messages |
|---|---|
| Subject | Cisco IOS Error %EIGRP-5-NBRCHANGE |
| Skill level | Intermediate (CCNA / CCNP background recommended) |
| DIY-able? | Yes if you have CLI access and a maintenance window. |
What does %EIGRP-5-NBRCHANGE mean?
EIGRP neighbor state changed.
Full fix path
If neighbor went down: check IP, AS number, hello/hold timers, K-values.
Spot the symptom
show logging
show running-config
show version
show platform | include status
Common related issues
| Symptom | Where to look next |
|---|---|
| Repeating message | Indicates a persistent root cause: fix the source rather than just clearing logs. |
| Paired error code | Cross-reference with the Cisco System Message Guide for the related codes. |
| Hardware suspect | Open Cisco TAC case with show tech-support bundle. |
Frequently asked questions
Will this configuration survive a reload?
Only after write memory (or copy running-config startup-config). On IOS-XE devices in install mode, the install commit is also required.
Is this safe to apply on a production network?
Test in a lab or a maintenance window first. Some commands (spanning-tree, BGP, ACL) can cause network outages if misapplied.
Where can I find the Cisco official documentation?
https://www.cisco.com/c/en/us/support/all-products.html, search the product family + the feature name.
Which IOS / IOS-XE version does this apply to?
The commands above were validated on IOS-XE 17.x family (Catalyst 9000) and IOS-XE 17.x (ISR/ASR/Catalyst 8000). Older trains (15.x for legacy IOS) may need slightly different syntax. check ? in the CLI.
Related guides
- All Cisco fix guides → /cisco/
- Cisco IOS error messages → /cisco/section/ios_error_messages.html
- Cisco troubleshooting by symptom → /cisco/section/troubleshoot_symptoms.html
References
- Cisco System Message Guide for IOS-XE / IOS
- Cisco Bug Search Tool: https://bst.cloudapps.cisco.com/bugsearch/
- Cisco Smart Software Manager: https://software.cisco.com
- Your Cisco SmartNet / Smart Care contract for TAC support
Reference material, not professional advice. Validate against your specific IOS-XE version and test in a non-production environment before applying.
Why this matters for your day-to-day
A Cisco 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 Cisco 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.
Confirm it stuck
On a Cisco 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 Cisco 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
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.
Should I update firmware first or last?
Update firmware first if a release note specifically mentions your symptom. Otherwise, finish the troubleshooting flow first, then update; that way you can isolate whether the update or the underlying fix solved it.
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.
Can I roll this back if something breaks?
Yes for software-level changes (firmware rollback, config rollback). Hardware changes are usually one-way. Always back up settings before starting.
Why is this happening on a brand-new unit?
Out-of-box defects do occur. If you've owned the device under 30 days and the symptom persists after a factory reset, escalate to the seller for replacement under DOA terms before opening a manufacturer support case.
Field notes from real incidents on Cisco IOS Error %EIGRP-5-NBRCHANGE
When I work on Cisco IOS Error %EIGRP-5-NBRCHANGE: Causes & How to Fix the rhythm I lean on is the one I have built over years of these tickets, not a stack of generic advice. Cisco bug search tool is the cheapest sanity check before a config change: search the symptom, sort by affected releases, decide. I never run a software upgrade on a live Catalyst stack without an out-of-band console session; the in-band session drops at the worst possible moment.
The newer Cisco IOS-XE traceability tools (show platform hardware fed) are massively underused; they answer questions the old CLI cannot. Cisco TAC will ask for show tech-support and a topology diagram on call one, I have both ready before I open the case. Most catalyst stack issues I have triaged were power-budget related, not software. the show power detail output answers it in 5 seconds.
Tools I actually reach for
For Cisco IOS Error %EIGRP-5-NBRCHANGE: Causes & How to Fix on Cisco IOS Error %EIGRP-5-NBRCHANGE the cheapest signal I can land usually comes from a known order of operations, not a kitchen-sink approach. I start with show tech-support (capture for TAC) because it is the lowest-friction way to confirm the failure is real and reproducible. If that returns ambiguous data, I escalate to show interfaces counters errors, ping vrf <vrf> <target>, show platform hardware capacity, show logging last 200, and finally to show running-config | include <feature> only when the cheaper tools cannot reach the layer the failure lives in. That ordering matches the failure surfaces I have actually seen on Cisco IOS Error %EIGRP-5-NBRCHANGE units over the last few years, not an abstract taxonomy. The cheap signals gate the expensive ones so the investigation does not balloon into a multi-hour exercise.
Verification I run before I close the ticket
Before I mark Cisco IOS Error %EIGRP-5-NBRCHANGE: Causes & How to Fix resolved on a Cisco IOS Error %EIGRP-5-NBRCHANGE unit, the verification loop below is what I actually run. Each step proves a different layer is green, and the order matters - the cheap checks gate the more expensive ones so I never burn an hour on a deep test that a shallow one would have failed in seconds.
show logging | include %LINK|%LINEPROTO|%BGP|%OSPFIf that one comes back clean, move to the next check. If it does not, stop and dig in there before layering more verification on top of a red signal.
show interfaces <int> | include errors|drops|CRCIf that one comes back clean, move to the next check. If it does not, stop and dig in there before layering more verification on top of a red signal.
show ip route <prefix> # confirm best path post-changeIf that one comes back clean, move to the next check. If it does not, stop and dig in there before layering more verification on top of a red signal.
show spanning-tree summary # confirm topology stabilityOnly when every line above runs clean do I close the ticket and update the runbook with the timestamps. A green verification that nobody can reproduce is not a fix, it is luck waiting to regress.
Where I check first when the docs disagree
When two sources contradict each other on a Cisco IOS Error %EIGRP-5-NBRCHANGE detail, the disambiguation order I lean on is stable across products and across years. Cisco TAC case knowledge base is where I start for the ground-truth view. cisco.com/c/en/us/support, official command references is where I start for the ground-truth view. developer.cisco.com for NSO / model-driven APIs is where I start for the ground-truth view. cisco.com/c/en/us/td/docs/ios-xml for IOS XR is where I start for the ground-truth view. Random blog posts and reseller wikis are signal, not ground truth, and I treat them as such until the references above either confirm or contradict the claim. The cost of trusting an unauthoritative source on Cisco IOS Error %EIGRP-5-NBRCHANGE: Causes & How to Fix is rarely worth the time it saved.
Pitfalls I have walked into on this exact path
The shortcuts that look smart on Cisco IOS Error %EIGRP-5-NBRCHANGE: Causes & How to Fix have a habit of biting back. The pitfalls below are the ones I have personally walked into on a Cisco IOS Error %EIGRP-5-NBRCHANGE unit, not things I read about. Most catalyst stack issues I have triaged were power-budget related, not software: the show power detail output answers it in 5 seconds. The newer Cisco IOS-XE traceability tools (show platform hardware fed) are massively underused; they answer questions the old CLI cannot. I never run a software upgrade on a live Catalyst stack without an out-of-band console session; the in-band session drops at the worst possible moment. When in doubt I revert to the slower path that the manual prescribes - the time I save by skipping it is always smaller than the time I spend cleaning up afterwards.
What I tell the next on-call
When I hand Cisco IOS Error %EIGRP-5-NBRCHANGE: Causes & How to Fix off to the next person on rotation, the three lines I leave in the runbook are these. First, the symptom signature on Cisco IOS Error %EIGRP-5-NBRCHANGE - not a paraphrase, the exact string that surfaces in logs or on the screen. Second, the diagnostic that gave the highest signal in the least time. Third, the exact verification command whose green output justified closing the ticket. That trio is what turns a one-off fix into a runbook entry the next engineer can use without paging me at three in the morning.
I also add a one-line note on the cost of getting this wrong. For Cisco IOS Error %EIGRP-5-NBRCHANGE: Causes & How to Fix on a Cisco IOS Error %EIGRP-5-NBRCHANGE unit, the cost is rarely the replacement part or the patch itself. It is the downtime, the second site visit, and the trust deficit you spend with whoever owns the asset when the fix does not hold. That framing keeps the next on-call from choosing the cheap-looking shortcut that ends up costing the most in elapsed hours and goodwill.
Related fixes
Related guides worth a look while you sort this one out:
- AnyConnect Secure Client EIGRP wide metrics 64 bit IOS XE compat: Fix
- ASR 1000 EIGRP wide metrics 64 bit IOS XE compat: Fix
- Catalyst 8300/8500 EIGRP wide metrics 64 bit IOS XE compat: Fix
- Catalyst 9200 EIGRP Wide Metrics 64 Bit IOS XE Compat: Fix
- Catalyst 9300 EIGRP wide metrics 64 bit IOS XE compat: Fix
- Catalyst 9400 EIGRP wide metrics 64 bit IOS XE compat: Fix
People also ask
Will this configuration survive a reload?
Only after `write memory` (or `copy running-config startup-config`). On IOS-XE devices in install mode, the install commit is also required.
Is this safe to apply on a production network?
Test in a lab or a maintenance window first. Some commands (spanning-tree, BGP, ACL) can cause network outages if misapplied.
Where can I find the Cisco official documentation?
https://www.cisco.com/c/en/us/support/all-products.html, search the product family + the feature name.
Which IOS / IOS-XE version does this apply to?
The commands above were validated on IOS-XE 17.x family (Catalyst 9000) and IOS-XE 17.x (ISR/ASR/Catalyst 8000). Older trains (15.x for legacy IOS) may need slightly different syntax. check `?` in the CLI.