With the speed networking demands goes-on, traditional administrators have started using Windows’ with 2 networks configured on 2 NIC’s with 2 default gateway’s as well. This is one of the thing which can never be predicted as to how windows will behave.

First of all, Windows is not made to make intelligent decisions if it is done intending to do failover/load balancing. So to say, it is an Operating System developed to make your experience better while working and not as a routing device.

The only time you can have 2 default gateway’s on any windows machine is when both the NIC’s are in the same network, otherwise you might see it working if you’re that lucky but it is unpredicted as to what’ll happen when.

So take the advise in Microsoft’s own words;

http://support.microsoft.com/kb/159168

http://www.microsoft.com/technet/community/columns/cableguy/cg0903.mspx#E3F

http://support.microsoft.com/default.aspx?scid=KB;EN-US;Q262397&ID=KB;EN-US;Q262397

Want more supporting info ? Just google for ‘Windows and 2 default gateways’ !

Let networking to be left with networking devices which are made for it and quit complaining about Windows not able to do it