ok to explain more, my internal network has IP network as 10.50.x.x with gateway as 10.50.x.254. Whereas my DMZ IP network should be 192.168.x.x with gateway as 192.168.x.254.
Now if I create a new vSwitch with DMZ IP network, the gateway for host remains as internal network gateway. So I am not able to communicate with DMZ machines.