What Is an IP Address Conflict?
an IP Address Conflict — the problem when two devices on the same network are assigned the same IP address — causing intermittent connectivity failures for both.
How it works
When two devices share an IP, the network can't reliably decide which should receive traffic — both may respond to ARP, confusing switches and causing dropped or misdirected packets. Symptoms are intermittent and confusing: connectivity that works then fails as the conflict shifts. Common causes are a static IP set inside a DHCP range, or two DHCP servers with overlapping pools.
Why it matters
IP conflicts are a classic troubleshooting scenario — recognising the "works sometimes" symptom and its causes (static-in-DHCP-range, dual DHCP) is practical networking knowledge. DHCP with proper exclusions prevents most conflicts. See how DHCP works.
Frequently asked questions
What causes an IP address conflict?
Two devices assigned the same IP — usually a static address set within a DHCP range, or two DHCP servers with overlapping pools.
What are the symptoms of an IP conflict?
Intermittent connectivity — it works then fails unpredictably — affecting both devices, since the network can't reliably route to the shared address.
How do you prevent IP conflicts?
Use DHCP with proper excluded-address ranges for static devices, and never run two DHCP servers with overlapping scopes on the same network.
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