Routing problem - wrong netmask on static route.

[SoonerIra]

so here's the config:

|local network| <-> T1 <-> |remote network|
| Privite Ip's |
| |
-----> Internet-pubIP's <------

We have our local network and server co-located at a data center accross town. We have firewalls between the local and remote networks and the internet and the T1 is connected behind the firewalls.

We can access it across the public internet by using one domain and accross the direct T1 by using another domain. Internally these domains resolve to their respective internal or external IP addresses.

The local network is: 10.8.8.0 gw 10.8.8.252
The remote network is: 10.8.9.0 gw 10.8.9.252

Until last week we were able to route correctly. We had an internet outage at our local network after which the problems started. During this the T1 between the two networks was unaffected.

Clients using DHCP get the static route from the DHCP server. Clients with static IP's have it configured on their machine.

the correct route on the local network should be:

Network Destination Netmask Gateway Interface
10.8.9.0 255.255.255.0 10.8.8.252 10.8.8.x

After doing an ipconfig /release ../renew, it will be:
Network Destination Netmask Gateway Interface
10.8.9.0 255.255.255.255 10.8.8.252 10.8.8.x

We have to manually delete the incorrect route and add the correct one.

Also it will change overnight as well, doesn't have to come with the ipconfig /release .../renew.

Where is it getting the incorrect netmask. Somehow it thinks that 10.8.9.0 is a host and not a network. I am running microsoft dhcp and it doesn't allow you to specify a netmask. just destination and gateway.

please help... I am begining to look stupid over here...

 

[aquias]

I'll preface this, with I'm not the pro around here but I can give you a few things to try...

First question, have you run a reconcile from the DHCP console? This will verify that the database and registry settings are consistent.

When you go to properties (again from the DHCP console) on the scope 10.8.8.x, what is the subnet mask listed?

Here is some more information that may be helpful as well...

http://support.microsoft.com/?kbid=255999

 

[SoonerIra]

I am pretty sure it's not DHCP... I have even completely removed the scope and recreated it like it was before...

I believe the client machines are getting the right information from the DHCP server just when it is adding the route and discovering the netmask it somehow is getting the wrong information...