Routing problem OR LanModem?

[bubarooni]

I have a problem which I cannot even properly describe. Here is my best shot at it:

I have a PIX 506 and a 1750 router at Site1.
I have a 1750 at Site2. Site2 is connected to Site1 w/ Frame.
I have a 1750 at Site3. Site3 is connected to Site1 w/
Frame.
I have a 1750 at Site4. Site4 is connected to Site1 w/ a site-to-site vpn over SDSL.

Each site has a server (actually win2k pro) that runs an app that management needs to be able to access from any other location.

At Site3 I am having a problem because the server is sitting behind a 3Com Lan Modem that is used to process claims via a vpn to a third party server. Every workstation at that site can access the application but it can't even be pinged from one of the other sites.

The target server has an ip of 192.168.3.3 and the lan modem has an ip of 192.168.3.2. I can ping the target server from the local router but any other router times out when trying.

Both the Lan Modem and the Server show up in the ARP table on the local router but neither can be pinged from a remote router or workstation.

Is it the Lan Modem or the router config? Any ideas would be greatly appreciated.

 

[bubarooni]

OK, here is a thought, though I don't know what to do with it. The server has a mask of 255.255.255.0. It is plugged in to the back of the LanModem which also has a mask of 255.255.255.0.

 

[yizhar]

HI.

> I have a PIX 506 and a 1750 router at Site1
How do they connect?
Is the pix 506 connected to another router and from there to ISP?
Or is the pix sitting between the 1750 and the local LAN at site 1?

It seems like a routing problem.
You should check and reconfigure routing tables on all devices along the path, including the hosts (W2K servers) themselves if needed.


Yizhar Hurwitz

http://come.to/yizhar

http://teachers.sivan.co.il/yizhar

 

[bubarooni]

The PIX has a cable modem connection and sits in front of the 1750 which is connected to Site2 and Site3 via Frame.

When I do traceroute commands to the Lan Modem (192.168.3.2)or server (192.168.3.3) at Site3 it always times out on the serial interface of the remote router (10.0.3.2). Any other address there resolves immediately after it hits the serail interface.

I can't seem to figure out an IP ROUTE command that will correct the situation. I have tried them on the Site1 and Site2 router. Am I barking up the wrong tree with the IP ROUTE command?

thanks

 

[yizhar]

HI.

OK, I got the picture of the main site, but still don't understand what's going on in Site 3 with the Lan modem.
Anyway as you already guessed the problem is probably there (lanmodem configuration - maybe some kind of NAT or other rules).
Check default gateway and routing table of the server and modem on Site3 (Yes you should check routing table also on the host itself!).

It seems like a routing issue not related to the pix.


Yizhar Hurwitz

http://come.to/yizhar

http://teachers.sivan.co.il/yizhar

 

[bubarooni]

The LanModem is connected directly to the local LAN at Site3. The server is connected to an ethernet port on the back of the LanModem.

The only purpose of the LanModem is to supply a dialup vpn to a 3rd party vendor so we can check insurance coverage, claims status,etc.

To make that work, I have to set the Default Gateway on the server to the LanModem rather than Site3's router. There is no place to enter a Default Router on the LanModem but I'm sure it's the ISP.

The thing that has me flustered is I can access the server at Site3 and do so crossing the LanModem but can't cross it when I try to access the server from Site1. I can't even ping the LanModem from Site1 for that matter.

There was a 3com KB article I read that said the LanModem doesn't support bridging. Could that be the problem?

 

[yizhar]

HI.

> The server is connected to an ethernet port on the back of the LanModem.
Again - this info does not give the full picture.
How many NICs on the server?

Why don't you have something like this:

[__________Site 3 SWITCH_________]
| | | |
3COM server workstations Cisco1750

Anyway, I think that all you need to do is to apply static routes on server in site 3:
route /?
route -p add .....
route print



Yizhar Hurwitz

http://come.to/yizhar

http://teachers.sivan.co.il/yizhar