DHCP server and wireless access point

[dvanzee]

When someone connects their laptop to our network (via wireless) and they have a home network with the address scheme 192.168.0.x it seems to cache (not static, dhcp) the old home ip address when it's brought onto our network kicking our servers offline. We have had this happen twice with 2 different laptops. My questions is, is there some way to prevent this from happening? Again the dhcp server does not assign this address it's something cached on the laptop. And it's only a network interruption of about 1-2 minutes while dhcp reassigns the laptop a new address. Any ideas or suggestions would be great

[Brandon Buffin]

Make sure the static addresses your servers use are excluded from the DHCP pool.

Hope this helps.

Brandon

[thisisshanky]

Like Brandon suggested, definitely make sure your DHCP pool has the static addresses for servers excluded.

I think the DHCP address (last address received) is stored somewhere in registry of the PC. I am not aware if there is a way to disable this feature on PC by editing registry.

=============Edited================

If you open regedit (Win registry)

HKEY_LOCAL_MACHINE->SYSTEM->CurrentControlSet->Services->

Under the appropriate NIC you should be able to see a subfolder name Paramters->TCPIP. Click on TCPIP and on the right hand side pane, you should see a paramter called IPAddress set to 0.0.0.0 (if using DHCP) and also another parameter called DHCPIPAddress -> this should show the value of the DHCP leased ip address for this nic. This value is cached here even if the nic is disabled or not connected to the wireless network. You can clear this entry incase you want to go this route.

Make sure you backup your registry files before you edit windows registry.

HTH

[MIKE DOUGLAS]

Put your servers and users in different VLANs/subnets. Easy fix if you have a switch that supports the L3 code.