ADSL Modem/Router sometimes hands out incorrect IP addresses
- by Peter Keevill
My setup is as follows:-
Main ADSL modem / router (switch) configured as DHCP server with address range 192.168.0.25-60
The office machines are configured with fixed IP ( not in the same address pool of course ) and hard wired to this router.
A wireless access point ( Router ) is connected to provide Internet access for guests in a separate area. This router is NOT configured as a DHCP server. Wireless authentication is turned off.
IP address lease times are set to 4 hours.
Sometimes guests are able to connect to the wireless access point but they are not given a valid IP. They get 169.x.x.x addresses.
Rebooting their machines does not resolve the problem.
The only way to resolve is to reboot the main ADSL/router which is often frustrating for other users who are successfully connected with valid IP and DG.
The problem seems to occur more frequently to Apple/Mac guests although it also sometimes occurs with Win machines.
I personally use Ubuntu on my Laptop and thus far, never have had any problem connecting and getting a valid IP address in the guest area.
One further point of note which may give a clue is that certain guests ( always Apple/Mac ) get lease times of 90 days. However, this does not 'stack out' the number of available addresses and of course, rebooting the router clears them until the next time they login.