hello
i am using a Realtek RTL-8139 ethernet controller.
i am able to use the internet and other networking services on a Windows OS without any problems.
But in a GNU/Linux system, i am not able to set my gateway entry to the one used in the windows environment.
my internet connection uses a static ip setting with the following entries used in windows:

ip address: 192.168.27.18
netmask: 255.255.255.0
gateway: 192.168.20.1
dns server: 192.168.20.1

i use Ubuntu GNU/Linux 5.10 and i tried both the GUI way and the command line way (using ifconfig and route commands). ifconfig doesnt report a problem. but when i do:

it gives a network unreachable error.
there is a web-based login system on the gateway system, which obviously doesnt work because the system doesnt ping to it at all.

even using another distro (i tried red hat linux also) didnt work.

i have been trying to solve the problem since a long time.
can somebody here please help me out.
thanks in advance.

I've noticed a similar "problem" in linux in the past. I think the issue is that, according to the netmask you've set on the interface, your gateway & dns server aren't on the same subnet as your PC. Windows ignores this, because its networking is sloppy, but Linux demands a correct netmask.

Basically, the admin of your ISP is lazy and probably doesn't understand IP subnetting.

Try changing your netmask to 255.255.224.0, and see if that helps.