Netmask and ip are incompatible in dlink dir-300

Question

I have Dlink Dir-300 wireless router. I have to set a static ip settings there. I specify Ip as 192.168.242.3 Netmask: 255.255.0.0. When I press enter it says that the ip is invalid. Although such configuration works on another(linksys) router normally.

When setting the static ip I have control only over last 2 bytes, first two are fixed, so we have 192.168.X.X according to our local network structure. My gateway must be 192.168.0.100.

When changing netmask to 255.255.255.0 then I get an error that the gateway and ip are not in the same network. When I change the netmask to 255.0.0.0 it doesn't show any error and saves the configuration, but there is no connection to the internet.

How can this problem be solved?

Answer 1

Using a client address of 192.168.242.3 with a subnet mask of 255.255.0.0. is a valid combination to give you a network address of 192.168.0.0 and all devices on the network would be using addresses of the format 192.168.x.x. It would, however, be more common to see addresses starting 192.168 used on so-called Class C networks (in the days of classful networking), which would mean that with a gateway of 192.168.0.100, all devices on the network would use a subnet mask of 255.255.255.0 and their addresses would be in the format 192.168.0.x. It might be worth checking whether this could be the case and then setting your router to a suitable address (eg: 192.168.0.99) to see what happens.

If, however, you are really sure that the network is setup with a network address of 192.168.0.0 and a subnet mask of 255.255.0.0 then this is still a legitimate way of doing things and it would be strange for the D-Link router to not recognise the adddress and subnet mask you specified - unless the router is somehow not allowing anything but rigid classful addressing - which in this day and age would be very peculiar.

It might be worth referring this problem to D-Link Tech Support for a comment, or perhaps first see if there are any firmware updates for the router.