Disabling default gateway assignment on selected NICs (Win7 / W2K8R2)

I'm new here, this is my first post, and I'm hoping someone can give me a useful answer...

I run a TV studio with a mixture of PC's and servers some running W2K3 server, and some running Win7 (both x86 and x64) and some running W2K8R2.

Each server, and most clients are connected via separate NICs to two distinct networks only one of which (intentionally) has an internet connection the idea being to provide a network for general administrative traffic and internet access separate from a network that is used for critical media applications. This approach has given good stability and security for 17 years.

It worked well in the XP, 2000 server, 2003 server days. Each server had its NICs configured on the OS not under DHCP) with the router/DHCP server assigning these referred IP addresses.

The problems came with Win7 and W2K8R2 both of which will only allow the user to cinfigure a etwork connection as a "work network" if the NICs are allowed to configure automatically via DHCP. If manually configured, the OS reports the network as "unidentified" anmd a Public network , which is untidy IMHO if it can be avoided. User intervention for the network identification anmd type (work/public/private) seems to be disabled if the nIC is configured manually in this weay.

Our previous reason for manual configuration (at least on the network that does not have internet connection) was to prevent the OS assigning a default gateway, which when set unnecessarily on a host which has two or more NICs installed can give conflicts.

Under Win7 and W2K8R2 such conflicts can still be avoided by manual configuration but at the expense of having the network defined as unidentified and Public.

I have tried to live with the tatus when onfiguring via DHCP but assigning a large (5000) metric to the respective network to jog the OS into trying the other network first. This works most of the time but not always.

I hjave also tried setting the registry paraneter

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\Tcpip\Parameters]
"DontAddDefaultGatewayDefault"=REG_WORD:00000001

To see if this will prevent the OS from assigning a gateway IP address when the nICs configure via DHCP, but it doesn't have any effect.

So the querstion is how can one allow automatic DHCP configuration of NIC's and prevent the OS from assigning a default gateway?

FYI, my routers (Netgear FVL328's) do not allow disabling a Default gateway configuration, even when here is no WAN connected to them.

Any help or advice would be welcome thanks!

Adrian

Welcome tothe forum. It may be simpler t turn off dhcp on the router and use a dhcp server like DHCP Server for Windows these make some good webservers and also a free dhcp server that ou can set gateway etc Tiny DHCP Server 1.3.5479 Review & Alternatives - Free download - Tiny Dhcp Service for Windows.

Thanks for the input. According the the Tiny DHCP helpenu -

Gateway and DNS Servers may be left blank. In this case program will use server's IP address instead

which also seems to be the default case with Windows if the NIC is set to DHCP and the router doesn't provide a gateway, the OS sets the routers address as gateway anyway, so It seems doubtful that this can be solved externally to the OS.

My thinking on this is that the solution if it exists is to find a way to tell windows not to set a default DHCP gateway for the specific NIC. This seems the only way that applications seeking an internet connectioon would only look at the NIC for which there is a valid gateway, leaving the NIC which doesn't have (and doesn't need) an internet connection bubbling safely in the background without any conflicts.

Having run two or more networks on my servers and workstations for many years, I can say thta the only time get conflicts is when the OS or application erroneously looks for the internet via a NIC that has an OS defined erroneous gateway set. If I can prevent this, then everything will be fine.

But how is the 64Kb question... )