Windows Server 2000 IIS goes down when connected to LAN

[aarellano]

Hello I would really appreciate some advice!!
I have a Windows 2000 server with IIS. The server has two nics one for the Lan and one for the WAN
We are using it as a webserver just for our reps.

Everything was working well and all of the sudden if the server is connected to the LAN nobody can access the server from the outside, but as soon as I unplug the LAN users can access the webpages. The problem is that I need the LAN connection, because the server is getting data from our db2 server. I have looked at the event viewer, fire walls and all seem to be in order.

 

[North323]

sounds like you got pOwned....
seriously, when did it start happening?
can you associate any changes to the time it started?
has anything changed on the nic settings?
any routing changes?
when did it start? who was logged in?
when connected to the lan, what is the error you get from the outside?
can the box still query your db2 server?

 

[aarellano]

it just started happening today, there has not been any changes in the server not the nic card, no router changes Administrator was the last one to log in.
When connected to the LAN it just says page cannot be displayed.
Yes we can still talk to our db2. I should also mention the db2 server is connected via vpn

 

[North323]

have you tried recyling IIS service? who is Administrator?

 

[aarellano]

I am the administrator and yes did that, it looks like it might be my sonicwall

 

[North323]

but if nothing changed, how could the sonice wall all of a sudden start to block traffic?

 

[aarellano]

hence my cry for help!! I have never seen anything like it. I did virus and malware scans and it came out empty the server has all the service packs so honestly I am a lost in here

 

[North323]

would anyone else sign on as adminsitrator?
is this a public site? can i get to it?
what does the infrastructure look like?

firewall - iis - db2 ?

have you verified your default gateway?
IP address on NIC cards?

 

[aarellano]

it is not a public site. we have a router, sonicwall, switch, server.

firewall on the server as well. I disabled the firewall and same thing. The gateways on both nics are correct. Hosts file has not changed

 

[North323]

have the routes changed on the router? what about the routes on the server, can you post a netstat -r

 

[itsp1965]

Is it possible that your IP subnets overlap on the two NICs (ie IP addresses within the same subnet range) which could explain why it's working when you have the other NIC disconnected? I have seen issues on Windows terminal services servers when this occurs

 

[aarellano]

itsp,
No, I don't believe so, because my static Ip addresses are from 1 to 100 and the dynamic are from 101 to 254

 

[itsp1965]

Yes but do they share the same network/subnet mask? in that case they are overlapping. On a multihomed server I have seen issues when the NICs themselves have IP addresses on the same subnet. Assign the NICs to different networks or change your subnet mask so it doesn't use the entire subnet.

 

[North323]

that would mean that someone changed it (probably not him) because he said this was working fine like two days ago..

check the IP address and the subnet. if you are saying 1 - 100 and 101-254 but the subnet is 255.255.255.0 then you have found your issue