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Docomon asked on

Wrong DHCP server

We are running a network on the 10.0.0.x subnet. We have another subnet on the DMZ of our Fortigate Firewall of 10.0.1.x

We have a wireless access point that is on the 10.0.0.x subnet.

We have a Windows 2003 SBS Server that is giving out IP's on the 10.0.0.x subnet.
The Fortigate is giving out IP's on the 10.0.1.x subnet.

We have ONE laptop that keeps getting an IP from the 10.0.1.x subnet but it says it is connected to the above WAP that is on the 10.0.1.x subnet.

If I plug the network cable in, it gets an IP from the server (where it should get an address). If I connected wirelessly, it gets an address from the 10.0.1.x subnet (which doesn't get to the server or have internet access).

I have taken my laptop, Android phone, iPad, etc. in his office and on ALL THREE wireless devices I get an IP address from the 10.0.0.x subnet.

Anyone have any ideas as to how I can fix this?
Internet ProtocolsLaptops NotebooksNetworking Hardware-Other

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Last Comment
Shane McKeown

8/22/2022 - Mon
Nick Rhode

Static Address?
Jon Covalt

Have you checked the server to see if it is, in fact, handing out an IP address to this laptop via the wireless?

If so, it could be that the laptop somehow has a reservation on the server's DHCP. You'll want to check that, as well as deleting the laptop's DHCP lease from the server and trying again via ipconfig /release and /renew, or just by rebooting the laptop afterwards.

It doesn't have a static IP address. Checked that also.
Your help has saved me hundreds of hours of internet surfing.

It's not getting an address from the server. That's the one I WANT it to get one from. It is getting an address from the Fortigate DMZ subnet. The Fortigate is giving out addresses on that subnet, however, the WAP that the laptop is connecting to is on the 10.0.0.x subnet (the right subnet). Strange issue!
Shane McKeown

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I moved where the WAP was plugged in (to a different switch that the DMZ wasn't plugged into) and the problem went away!

I will monitor this for a few days to make sure the issue is resolved for sure but it appears to be fixed!
Shane McKeown

Good stuff...glad to assist.
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