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Clients unable to access internet 1

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frankcpl

Technical User
Mar 16, 2007
77
US
I have an issue on my server 2003 R2 that is very puzzling. I have to set static IP address on client computers so that they are able to access the internet. If I set the DNS server and use the DHCP feature for the IP Address I have access to all internal resources, (server apps, shared files, network apps, ect) but cannot access the intranet.
Any help??
 
Yes DNS Fowarder is pointing to ISP DNS on oubound nic only, the intranic points to itself.
 
Couple of troubleshooting points:

1. Can you browse the web from the server. (Just try the one page, e.g. google.com)

2. From the clients, drop to a command prompt and run nslookup. From there your servers IP should be listed. At the new style prompt type in a URL such as See if it returns the IP.

If you fail step 2, and the client NSLOOKUP cannot resolve an external IP from your DNS server then your DNS server is not resolving correctly and as such is either not correctly connected to the internet or probably has the wrong IP forwarders.

If those tips don't help, try the DNS log on the server. If you want to confirm that it really is the server, from the NSLOOKUP prompt try typing in SERVER followed by the IP address of another external DNS server such as your ISP's.

If you can resolve OK but cannot access anything still try running TRACERT from the normal command prompt followed by a URL such as Follow the trace and see where is breaks. (I'd image at your router/firewall/modem)

Good luck,




Steve.

"They have the internet on computers now!" - Homer Simpson
 
Here is what I have found.
When I use the use DHCP for IP address then the nslookup pulls the servers ip and name. I can then pull the goole ip address from that prompt. The problem is when I use the tracert at the regular command prompt I get the destination is unreachable.
Where I am going wrong
 
OK, so when using DHCP you can resolve IP addresses?

If so, then it's not DNS, it's a routing issue. Check the gateway that your clients are using. (try IPCONFIG at the command prompt) The gateway should be router / firewall / modem - whatever the internal IP address is of your internet connection.
(E.G. we have a firewall, and a modem from the firewall that then plugs into the phone line for our ADSL. We would use the IP address of our internal port on the firewall. The firewall will route the traffic to it's WAN port, then the next hop is the LAN of the modem. The modem routes to the WAN which is the ADSL circuit)

If you're still not too sure. On your DHCP client, type in the following at command prompt:

route delete *
route add 0.0.0.0 mask 0.0.0.0 x.x.x.x

the x.x.x.x is the IP of your gateway. E.G:

route delete *
route add 0.0.0.0 mask 0.0.0.0 10.3.1.254

(If 10.3.1.254 is the internal IP of your router/firewall)

Then try another TRACERT and see where it goes.

If that's working then you need to change the settings on your DHCP server to add a default gateway that is valid and correct.

If you need more help let me know and i'll try to explain it a bit better! :)

Good Luck,




Steve.

"They have the internet on computers now!" - Homer Simpson
 
Thanks for the reply. I will jump back on this as soon as possible. I have an issue with Limewire that "just appears out of the blue" ever so often. Thanks for all you help again.
 
Mr. Steve,

I wanted to let you know that I really appreciate the time you spent working with me. I did the route delete and add route. That allow the client to access the internet, of course when I restarted it was back to not allowing the internet access.

I have looked at page after page on how to fix this issue and wanted to know if you might be willing to help me again.

I have set the default gateway on the server to 192.168.0.1 or at least I thought I did. Can you explain how to make these changes?
Thanks
 
frankcpl,

If you just want to add that route to the pc permanently, include a -p in your route add statement --

route add -p 0.0.0.0 mask 0.0.0.0 10.3.1.254

(If 10.3.1.254 is the internal IP of your router/firewall)

kmills
 
Thanks for the reply, sorry for the delay in responding. What setting am I missing on the server so that I will not have to go to all the machines and permenantly add the route to all the clients?
Thanks for the help.
 
I know this thread is getting old, but I still haven't figured this out. can someone please explain how to set the servers gateway so that I will not have to manually input IP Addresses into the NIC Properties?
 
Frankcpl,

Can you provide more details about your setup to help troubleshoot this?
Is the Windows 2003 Server in question the Domain controller for your domain? Is it also the DHCP server and the DNS Server?
What router/firewall are you using to access the Internet and is it through DSL, cable, T1?

In short, the DHCP server should have an IP pool of addresses set up to hand out, have the DNS address of your domain controller as the DNS server and the IP address of your router as the default gateway. Your internal DNS server should be set up to forward requests from you ISP dns servers.
 
It is a windows server 2003. It is also set as DC and DNS with a second DNS server in another location on the same network. It is connected straight to a cable modem.

I have set the IP pool, foggy on the DNS address of DC, except I do have the NIC with a static IP on the internal side with the primary DNS as the DC on both Servers. The second NIC is set with an DHCP address from the ISP with the primary and alternate DNS going to the ISP.

I have tried to find out why it worked for a while and now requires my to manually enter the IP Address and DNS entries into all client computers.
 
Sounds like you are using the server as the router also. What device is handing out DHCP for the local network? Is it also this server? It just sounds like you are missing something from the DHCP settings.

The clients default gateway should be the IP address of the server, which I think you mentioned is 192.168.0.1. Run ipconfig/all on a client that is set for DHCP as Steve suggested and post the results here.

Thanks.
 
Sorry for the delay. The office has been on vacation and I am just now able to gain access to the server again. This is the requested information. Any ideas on why I have to manually set all IP Adreesses before the clients can gain access to the internet?

Microsoft Windows [Version 5.2.3790]
(C) Copyright 1985-2003 Microsoft Corp.

C:\Documents and Settings\Administrator.FBCOB2>ipconfig /all

Windows IP Configuration

Host Name . . . . . . . . . . . . : FBCMAINSERVER
Primary Dns Suffix . . . . . . . : fbcob2
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : Yes
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : fbcob2
hsd1.ms.comcast.net.

Ethernet adapter Private:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Broadcom BCM5708C NetXtreme II GigE (NDIS
VBD Client) #2
Physical Address. . . . . . . . . : 00-18-8B-4C-D4-FB
DHCP Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 192.168.0.1
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . :
DNS Servers . . . . . . . . . . . : 192.168.0.1

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . : hsd1.ms.comcast.net.
Description . . . . . . . . . . . : Broadcom BCM5708C NetXtreme II GigE (NDIS
VBD Client)
Physical Address. . . . . . . . . : 00-18-8B-4C-D4-F9
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IP Address. . . . . . . . . . . . : 75.64.131.128
Subnet Mask . . . . . . . . . . . : 255.255.248.0
Default Gateway . . . . . . . . . : 75.64.128.1
DHCP Server . . . . . . . . . . . : 68.87.68.16
DNS Servers . . . . . . . . . . . : 68.87.68.162
68.87.74.162
Lease Obtained. . . . . . . . . . : Monday, June 11, 2007 6:22:34 AM
Lease Expires . . . . . . . . . . : Friday, June 15, 2007 6:22:34 AM

C:\Documents and Settings\Administrator.FBCOB2>
 
It looks like the private NIC is missing a default gateway entry. It needs to know it's next hop to access resources outside of the LAN. I think for your setup the default gateway should be the IP Address of the WAN NIC.
 
Do you need a gateway for your nic with the 192.168.0.1 addy?
 
Gah sry pg i was probably submitting just after you.
 
Sry for the delay in responding. If I put the outgoing nic IP in the gateway octet, then do I also put the same IP in the DNS as well.
 
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