How to route traffic from NIC1 to NIC2 when both NIC's are in different subnets?

I am implementing anycast ip on multiple servers which have 2 NIC's installed

NIC 1 is connected to the production LAN with a subnet and a Default Gateway (automatic registration in DNS enabled for the Servername) NIC 2 has only the anycast address (172.17.71.255/32) without a Gateway.

In IIS 8 I have created a web application which only listen to the anycast address.

When the second NIC is disabled and the anycast address is add to the first NIC, the web application works but when I enable the second NIC and add the anycast it doesn't work anymore. All traffic is going over the same gateway.

How can I route the anycast traffic from NIC1 to NIC2?

Rene

Posted 2014-10-02T17:59:26.617

Reputation: 11

Use route to setup a route (tricky , eh?). ;) – Ƭᴇcʜιᴇ007 – 2014-10-02T18:00:56.973

Or set the anycast as a loopback (unsure if you can on Windows though) and use your network equipment to route the anycast IP at the real addresses of devices providing the anycast service. It would be good do do some further research on anycast and how it works. – cpt_fink – 2014-10-03T07:29:35.133

Answers

If you have configured routing and firewall, enable broadcast routing:

Launch cmd as Administrator and run:

reg add HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters /v ForwardBroadcasts /t REG_DWORD /d 0x1 /f
reg add HKLM\SYSTEM\CurrentControlSet\Services\RemoteAccess\Parameters\NetbiosGateway /v EnableBroadcast /t REG_DWORD /d 0x1 /f

STTR

Posted 2014-10-02T17:59:26.617

Reputation: 6 180

Is this even a good idea? Messing with broadcast traffic without a complete understanding of your network and goal is usually painful. – cpt_fink – 2014-10-03T07:35:01.017

@cpt_fink Of course it is bad and can only be used on the local network. However, the application is written for broadcast traffic. Well, quite simply, you can return everything to its original configuration. Thanks for the good point. – STTR – 2014-10-03T20:12:08.120