Forum Discussion
Gateway IP address conflicts
Tmobile Gateway router HHCP seems to be assigning unique IP addresses on network devices but getting network warning of IP address conflicts every few minutes?
You can open a console/terminal and ping the network broadcast address 192.168.12.255 and then check the client's ARP table (command arp -a). That should provide some idea of clients that are up and are responding. If you have set any static IP addresses on the network in the 101-254 range then remove the IP for any client with a static IP in that range and use an IP from 2-100. I am pretty sure the DHCP scope runs from 101-254. I never seen an IP assignment below 101 from DHCP. I can assign and I do assign static IPs below 100 so I am pretty sure it is safe to say it is ok and will not duplicate any IP addresses. You can easily test by pinging an IP address you want to set from a client that is connected with a valid IP address. If there is no response then the IP is probably free, assuming it is NOT part of the DHCP scope.
Thanks for all the suggestions regarding the "Windows has detected an IP address conflict" on all PCs on the LAN. I should have provided my LAN setup...
T mobile Arcadyan KVD21 Gateway Router (excellent 5G signal and speed).
Netgear 16 port switch (directly connected to router).
About 10 windows 7 or 10 computers connected to the Netgear switch via ethernet
Few T mobile cell phones intermittently connecting via 2.4 GH wifi.
No additional router on the local network.
I wasn't aware the device allows for static IP addresses. A printer may have connected via a fixed IP address using the printer setup software, however.
All the windows computer devices showing windows IP network conflicts every five minutes.
Devices populate and seem to have unique IP addresses all in the allowed range as best I could tell by looking up each PC address.
The conflicts did not occur with prior fiber and copper routers using the same network configuration.
Internet Protocol Version 4 (TCP/IPv4) is set to Obtain an IP address and DNS server address automatically on each PC.
Rebooting the router and switch fail to stop the conflicts.
Releasing and renewing IP Addresses on each PC failed to help.
T mobile support suggested the windows computer IP address conflict error relates to frequent transient loss of connectivity (? the timer function mentioned above) with conflicts arising from the Arcadyan KVD21 Gateway DHCP frequently reassigning addresses. She suggested splitting the networks (2.4 and 5 GHz) to minimize IP address conflicts when reassigned. I'm not confident this would work.
