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rkozel

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Outlook and ISA Server, DNS Error?

Hello all, this is urgent and I appreciate the help!

I have SBS 2000 installed with ISA 2000 running. All my clients can get out to the internet and communicate with everyone else's machines on the internal network with no problems, i.e. server shares and printers, and everything is rosey as far as that's concerned.

The problem I am having is routing Outlook Internet Email through the Firewall to send and retreive email through an external provider on the client machines.  I am also unable to ping or telnet to the pop servers on the external domain(internet) from the client machines.   I have read numerous articles on this and created the IP Packet filters for ports 80, 25, 110, etc. to no avail.  The server itself has no problems with connecting to the pop and smtp servers via outlook or telnet.

Now I'm leaning towards maybe my DNS setup for the private network might not be correct.  If it's not the DNS can someone help?  I have listed the setup below in the order of connections, can anyone tell me what's wrong?  The SBS contains two NICs, one for external, one for internal and the SBS is also functioning as the DNS for the internal domain.

 ISP
 ISP Cable Router
 External Network Card on SBS Server Configured with ISP Static Address, subnet, gateway and DNS Servers
 Internal Network Card on SBS Server Configured with:
                                              IP:           192.168.1.10
                                              Subnet:    255.255.255.0
                                              Gateway:  192.168.1.1
                                              DNS:        192.168.1.10
Internal Router:
                                              IP:            192.168.1.1
                                              Subnet:     255.255.255.0
                                              Gateway:   192.168.1.1
                                              DNS:         192.168.1.10
Client Machines:
                                              IP:            192.168.1.X
                                              Subnet:     255.255.255.0
                                              Gateway:   192.168.1.1
                                              DNS:         192.168.1.10


If everything looks ok, can someone please guide me further, my clients need this access ASAP.

Thanks,
rkozel
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WeHe
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you have to configure the ISP DNS servers as forwarders in your internal DNS.
you should point your SBS's DNS Settings to itself too, the forwarder should do the internet resolution.
if your SBS (DC) points to another DNS, you will have troubles sometimes.
when you point your external NIC to use internal DNS dont forget to uncheck "Register this connection in DNS" for this NIC in TCPIP-DNS-Settings.
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rkozel

ASKER

Thank you, will give this a try this afternoon.  I apologize for sounding a little nieve here, but, how do I configure the ISP DNS servers as forwarders?  Can you tell me what settings to use for the internal and external nic's?
one correction:
External NIC can stay as it is. internal too.
just add the forwarder to your DNS Server:
Open DNS Management -> left click on your server -> right click your server -> properties -> forwarders -> Add the ISP DNS Servers at "Selected domain's forwarder IP address list:"
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ASKER

Hi, I checked this just now and the forwarders are already there.  Anything else I can try?
"telnet YOUR.MAIL(SMTP)SERVERS.NAME 25" (e.g. "telnet mail.mydomain.com 25") does not work?
"telnet telnet mail.mydomain.com 110" does not work too?
are you sure, you have configured ISA to let these ports go out on TCP?
what does "tracert mail.yourdomain.com" report?
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ASKER

Well, it resolves the IP address to the remote server, but it looks like it's getting stuck at the router?!?  Won't go past the 192.168.1.1, destination net unreachable
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WeHe
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ASKER

AMEN!  Thank you soo much for your help.  You helped me pinpoint it to the router and I was able to determine that the router was set to be used as an internet gateway.  That's why the requests were stopping there.  I was able to reconfigure it as a pass through router and reset all the clients to use 192.168.1.10 as the gateway, and a half hour later, Viola!  

Everything works fine.  Thank you so much again!  :-)