What this page covers
Record the duplicate symptom and locate the address authority before changing pool settings.
Step-by-step workflow
- Record the conflicting address and affected interfaces without publishing it.
- Check whether a second router, extender or hotspot is connected.
- Compare DHCP reservations with manually configured clients.
- Move one conflicting device to a documented automatic profile and retest.
Decision table
| Check | What it tells you | Safe next action |
|---|---|---|
| Two devices report same IP | Duplicate assignment or manual override | Inspect reservation and static settings |
| New router added | Two DHCP authorities may exist | Use one intended LAN authority |
| Conflict after sleep | Lease or resume state may be stale | Renew and verify the lease |
Limits and verification
MAC addresses and private IPs are sensitive operational data. Keep evidence private and avoid assuming malicious activity from one conflict.
Official sources
- IETF RFC 2131 — Dynamic Host Configuration Protocol (DHCP message and lease concepts)
- CISA — Securing Home Network Devices (home-network safety guidance)
Related Router Portal guides
Find the current gateway · Router security guide
Keep in mind: Firmware, operating-system menus, ISP policies and regional radio rules can change. Confirm the current official source and exact device before applying a setting.
Our networking steps are lab-tested against standard RFC 1918 private networking protocols across Windows 11 (24H2), macOS Sequoia (15.1), iOS 18, and Android 15. We verify physical device labels and firmware release documentation before publishing gateway instructions. Router Portal is strictly read-only and never requests, intercepts, or logs router passwords.