# Dual Network nics not routing



## frieatlast (Jan 26, 2006)

Setup: I have a windows 2003 web server with dual nics. One nic is set to give access to the internet through a firewall. This allows users outside the internal network access to web apps. The other nic is pointed to the internal network. This lets internal users and systems access the webserver directly from the internal network. Both nics are on seperate ip ranges. (Eg, nic 1 internal network 192.168.10.20/24 Gatway: 192.168.10.1 nic 2 internet 192.168.12.20/24 Gatway: 192.168.12.1)

Problem: (Both NICS are enabled)
1. Internal user accesses a webpage on the server. No Problem seeing the webpage. 
2. User enters username and password to access webpage apps. Webpage comes back with error. Is not able to find data. (The webpage is making a call to another server to pull the data from and bringing the data back for the user to view on the webserver)

3. I disable nic 2 (which is the nic going to the internet) and enter username and password, the webpage comes back with the correct data.

It looks to me as the routing for the webpage is working, but when both nics are enabled the call that is made to the other server to gather the data is not. 
I think it is trying to access the data from the internet connection which will have no chance of working. Is there a way to correct this issue by adding some sort of routing table?


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## jimscreechy (Jan 7, 2005)

This sounds like a domain problem.

It sounds like you have an internal and exteranal/internet domain with the same name. example test.com internal and external

with one card working (internal) it goes to test.com (which it correctly resolves internally) and finds the correct page... no conflict. 

2 cards enabled test.com becomes interanal and external. If dns is pointing to test.com for external routing, ie default gateway, it routes the packets externally, but perhaps because this domain is unregistered it cant resolve or it routes the packets back to the registered address which may be configured differently for external users... but infact this isn't an external source ie security fails. 

to be certain need more information about your setup. can i assume your routing between the two cards? or is there some other manner in which your hosts are reaching the internet. a diagram would be a great help.


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