Demand-dial routing

  • Thread starter Thread starter Vjekoslav Babic
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Vjekoslav Babic

Hello everybody!

I have a problem with RRAS demand-dial routing, and I am not sure if it can
even be solved with current network layout I have.

There are two networks, let's them call local and remote. Local is
192.168.1.X, remote is 10.40.0.X. Remote network has a third-party hardware
ISDN router to which I am trying to connect. Local network has a Windows
Server 2003 (named remote-gateway) computer with ISDN adapter and RRAS
service configured with demand-dial network interface to remote network. I
also configured NAT for remote network demand-dial interface.

When I establish the demand-dial connection through RRAS console, I can
connect to any server on remote network from Windows Server 2003 computer
that established the connection.

Using RRAS console, I also configured a static route to remote network
through demand-dial interface. On the local network default gateway computer
(named internet-gateway, which also runs RRAS and connects our local network
to the internet) I configured a static route to remote network through local
interface (this is to avoid deploying a static route to all local network
computers). When I tracert an address on remote network from any computer in
local network (other than remote-gateway), I get routed correctly all the
way up to remote-gateway computer, but then it stops. Here is the output:

C:\Documents and Settings\Administrator>tracert 10.40.0.11

Tracing route to 10.40.0.11 over a maximum of 30 hops

1 <1 ms <1 ms <1 ms internet-gateway [192.168.1.1]
2 <1 ms * * remote-gateway [192.168.1.23]
3 * * * Request timed out.

I am able to ping the RRAS demand-dial interface's IP address (10.40.0.90)
from anywhere within the local network. However, when I try pinging any host
on remote network, the packets are lost and no response is received.

As I am able to understand from MS documentation (Technet and Windows Help),
I can establish a one-way initiated demand-dial connection if answering
router is also a Windows 2000/2003 computer running RRAS. My question is, is
there a way to configure demand-dial connection with or without NAT which
would support my current two networks as they are (replacing the existing
hardware third-party router with Windows 2000 RRAS machine is not an
option).

Any response would be highly appreciated!
 
As far as routing is concerned, everything looks fine at your end. The
problem is probably at the other end. The ISDN router knows how to reach
your RRAS server (using its 10.40 IP), but it will not know what to do with
a 192.168.1.x address. It will send this traffic to its default gateway. So
it is probably sent to the Internet and dropped or lost.

To route between 192.168.1.0 and 10.40.0.0 , this router needs to send
traffic for 192.168.1.0 back through the ISDN link. (On a RRAS router, you
would use a demand-dial interface, link the route to it and connect to the
dd interface by name). I can't really advise on how you do it on your
router.

If you can't program the remote router, you should be able to get it
working using NAT on your RRAS router. Configure the LAN interface as
private and the demand-dial interface as public. All traffic going to the
remote site should then use the RRAS router's "public" IP, which the remote
router knows about. The clients should be able to ping any machine that the
server can ping.

Vjekoslav Babic said:
Hello everybody!

I have a problem with RRAS demand-dial routing, and I am not sure if it can
even be solved with current network layout I have.

There are two networks, let's them call local and remote. Local is
192.168.1.X, remote is 10.40.0.X. Remote network has a third-party hardware
ISDN router to which I am trying to connect. Local network has a Windows
Server 2003 (named remote-gateway) computer with ISDN adapter and RRAS
service configured with demand-dial network interface to remote network. I
also configured NAT for remote network demand-dial interface.

When I establish the demand-dial connection through RRAS console, I can
connect to any server on remote network from Windows Server 2003 computer
that established the connection.

Using RRAS console, I also configured a static route to remote network
through demand-dial interface. On the local network default gateway computer
(named internet-gateway, which also runs RRAS and connects our local network
to the internet) I configured a static route to remote network through local
interface (this is to avoid deploying a static route to all local network
computers). When I tracert an address on remote network from any computer in
local network (other than remote-gateway), I get routed correctly all the
way up to remote-gateway computer, but then it stops. Here is the output:

C:\Documents and Settings\Administrator>tracert 10.40.0.11

Tracing route to 10.40.0.11 over a maximum of 30 hops

1 <1 ms <1 ms <1 ms internet-gateway [192.168.1.1]
2 <1 ms * * remote-gateway [192.168.1.23]
3 * * * Request timed out.

I am able to ping the RRAS demand-dial interface's IP address (10.40.0.90)
from anywhere within the local network. However, when I try pinging any host
on remote network, the packets are lost and no response is received.

As I am able to understand from MS documentation (Technet and Windows Help),
I can establish a one-way initiated demand-dial connection if answering
router is also a Windows 2000/2003 computer running RRAS. My question is, is
there a way to configure demand-dial connection with or without NAT which
would support my current two networks as they are (replacing the existing
hardware third-party router with Windows 2000 RRAS machine is not an
option).

Any response would be highly appreciated!
Click to expand...
 
If you can't program the remote router, you should be able to get it
working using NAT on your RRAS router. Configure the LAN interface as
private and the demand-dial interface as public. All traffic going to the
remote site should then use the RRAS router's "public" IP, which the remote
router knows about. The clients should be able to ping any machine that the
server can ping.
Click to expand...

I did configure NAT as you said, but it still didn't work. I will try
configuring the remote router, it seems the only way now.

Thank you very much for your reply!
 
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