Server 2003 R2 Keeps Losing Internet Connection

[livpie]

I have not previously configured a server with Internet access so I may have missed something that should have been simple to do.
Here is what I have...
Server 2003 R2
2 NICs
DSL Router

I connected the server to one of the ports on the DSL router and went back in a reconfigured network access using NAT. Everything seemed to working properly but then I just started losing Internet connection to both the server and all the workstations connected through the server.
I tried using a static IP and a dynamic IP and I keep getting the same problem where it will lose Internet connection.

I am able to restore the connection if I go into the network connections and do a repair on the network adapter. This only works temporarily though and I have not been able to pin point what is causing the Internet connection to stop working.

Any ideas would be greatly appreciated.

Thanks!
Tom

 

[datagnostic]

Can you find any leads in the server's event viewer?

What kind of DSL router are you behind?

Is the server acting as a gateway to the workstations behind it?

For servers, try to always use manual IP configuration and use an IP address that's in your DHCP exlusion list. That way you can rule out duplicate IP's.

A logical diagram would be useful

 

[YeOldeStonecat]

You always want static IPs....but since you already have a DSL router at the edge......why double NAT it with Windows ICS? (yuck!). Double NAT makes for a messy network..and Windows ICS (or Servers RRAS version)...yuck.

Hardware router appliance at the edge doing NAT.
Single NIC the server and have the entire network protected by the router.

But yes....static IPs on both red and green NICs of the server.
What settings do you have on them? IP, subnet, gateway, DNS.

 

[livpie]

Thanks for the replies. I thought I was not using ICS when I chose the NAT option in the setup.

The IP settings for the server are:
192.168.0.254
255.255.255.0
DG 192.168.0.254
DNS 192.168.0.254

The IP settings for the network card with Internet on the server are:
192.168.254.200
255.255.255.0
DG 192.165.254.254
DNS 192.168.254.254

 

[datagnostic]

Some small stuff that doesn't look right, see if this helps:

The IP settings for the server are:
192.168.0.254
255.255.255.0
DG 192.168.0.254
DNS 192.168.0.254

You should set your DNS to 127.0.0.1 to refer to self.
Leave the default gateway blank, as it's just referring to itself again.
Is the server acting as a router for the internal hosts?

The IP settings for the network card with Internet on the server are:
192.168.254.200
255.255.255.0
DG 192.165.254.254
DNS 192.168.254.254

Your default gateway is not in your subnet, but I suppose that's a typo.
The DNS server 254.254, is that the upstream router? Do you have an internal DNS server?

 

[livpie]

I updated the settings on the server as you had directed.

The server is assigning DHCP to all the workstations. I am not sure if that means it is acting as a router but I assume that was what your question meant.

I just went into one of the workstations and changed the DNS server to 192.168.254.254 and left the IP as dynamic. I am thinking that maybe it is a DNS issue.

You were correct on the typo.

Thanks for the help!
Tom

 

[datagnostic]

Tom

Under your DHCP scopes, one of the options is "default router". If that IP is the same as your server's NIC, it's acting as the default gateway for the LAN devices.

I would personally leave the routing to the router though, but ofcourse there might be a specific reason why it's not the case here...

 

[Luis Rodriguez]

Under the DHCP role, make sure you are sending out both the local dns to the server and the dns to the www. I'm still fairly new to the networking game, but i had to fix this issue this morning myself. i have dhcp sending out DNS 10.0.0.1 (my server) and DNS 4.2.2.2 (for www)

 

[YeOldeStonecat]

Under the DHCP role, make sure you are sending out both the local dns to the server and the dns to the www. I'm still fairly new to the networking game, but i had to fix this issue this morning myself. i have dhcp sending out DNS 10.0.0.1 (my server) and DNS 4.2.2.2 (for www)

DNS for the clients should be the domain controller(s) LAN IP only.

I've seen some people add a public DNS server (such as the ISPs, or some other public DNS servers) as a secondary DNS server to hand out to clients...so that they can surf he net if the DC is down. But...your DC shouldn't be down. If you need redundancy, have a second DC. Setup your DCs DNS to have good public DNS servers (such as OpenDNS) as their forwarders. Check out my DNS/DHCP guide here...it's dated (uses SBS03)..but still valid.
http://www.speedguide.net/articles/server-based-network-guide-1660

 

[Luis Rodriguez]

DNS for the clients should be the domain controller(s) LAN IP only.

Sorry for the misinformation then, don't mean to get off topic, but that was my fix for workstations not being able to connect to the internet.

 

[YeOldeStonecat]

Sorry for the misinformation then, don't mean to get off topic, but that was my fix for workstations not being able to connect to the internet.

I suspect on the server you faced...DNS wasn't functioning properly on the DC..so when it was handed out to the clients....their requests weren't being processed correctly...something was broken there. Perhaps it's DNS forwarding was set to stale/no longer functioning public DNS servers.