Force Windows Local Subnet Traffic through a Gateway
- by Beerey
Hi all,
We are attempting to route all traffic from a certain machine to a gateway. This works ok for traffic destined for subnets outside of the machine's subnet. However, traffic to machines in the same subnet as the source machine goes through an On-Link gateway in Windows. This means that the default gateway is ignored, and traffic in a subnet (for example, 192.168.50.10 - 192.168.50.11) flows.
Destination Netmask Gateway Interface Metric
192.168.50.0 255.255.255.0 On-link 192.168.50.214 276
This route can be deleted from Windows, but when the machine is rebooted it always comes back.
Adding a persistant static route to the gateway with a lower metric doesn't work, since it will still try the On-Link gateway after the persistant route fails.
Adding each machine in a VLAN isn't an option due to the setup we have
Adding a startup script to delete the gateway isn't a great option either, since users will have full admin access to the machine and might disable the script.
We cannot transperantly intercept all network traffic on the subnet using Gratuitous ARPs or transparent proxying, since there are other machines on the subnet which use a different gateway
The only way we have gotten it to work is by adding a persistant route to the gateway for the subnet traffic, and deleting the On-link route on reboot.
The question is then.
Is there a way to permanently remove this On-link route
If not, is there a way to otherwise force even local subnet traffic to go through a gateway?
