How can I allow two networks to talk?

f1y

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I have my modem then a switch, and two gateways a Cisco 800, and a sonicwall tz170.

The Cisco isn't managed by me, it's on a 172.18.2.x subnet and I only have about 12 addressable IPs.

I manage the sonicwall and have all 254 addresses open. The computers have to stay behind the Cisco because it connects to a VPN that the line of business software uses.

I can't connect the two gateways by VPN because I cant control the Cisco.


How can I get these two to talk? I have a new server on the sonicwall network and an old server on the Cisco network. I want the computers to be able to see both servers
 
I have my modem then a switch, and two gateways a Cisco 800, and a sonicwall tz170.

The Cisco isn't managed by me, it's on a 172.18.2.x subnet and I only have about 12 addressable IPs.

I manage the sonicwall and have all 254 addresses open. The computers have to stay behind the Cisco because it connects to a VPN that the line of business software uses.

I can't connect the two gateways by VPN because I cant control the Cisco.


How can I get these two to talk? I have a new server on the sonicwall network and an old server on the Cisco network. I want the computers to be able to see both servers

can you create a vpn from the cisco ( servers on that side ) to the sonic wall ?

What about a patch cable from the cisco to the sonicwall with it's own zone ?
 
Is there a reason you don't want to stick everything behind the Cisco? Are you wanting to use the Sonicwall for features other than just routing?
 
The main problem is going to be figuring out why they can't talk now. Are you able to ping or arping the Cisco from the Sonicwall? Is there any kind of debug on the sonicwall that lets you look at the raw packets it's getting?

Is replacing the switch with a hub a possibility?
 
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only 12 IPs on the inside of that Cisco? Why? What is its subnet?

I would get an old router maybe a 2651xm if its a small business or a 1841 if its med size and use it to route between the subnets.
 
I would get an old router maybe a 2651xm if its a small business or a 1841 if its med size and use it to route between the subnets.
Why would that be needed? The routers are directly connected (same L2 network) and should not require another router between as far as I know?
 
I assumed they where different subnets.

I see what you mean now, you will probably need static routes to do what you want.
 
I assumed they where different subnets.

I see what you mean now, you will probably need static routes to do what you want.

wouldent you be able to create a new subnet on x4 of 172.18.2.x subnet keep the dhcp server off and connect the cisco to the sonicwall with a cable ?

then create a rule for the other zone/subnet on the sonicwall to talk to the new one on x4 that talks to the cisco ?


Thought..
 
it sounds like there are 2 ADSL lines here though so I am thinking they want to use one for internet but still be able to ping over the VPN to the other side. The VPN will only be accessable if the default gateway for the PCs is the Cisco becuase the Sonicwall knows nothing about the VPN ip range. The sonicwall needs a static router adding to say for this ip range go to this gateway.
 
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it sounds like there are 2 ADSL lines here though so I am thinking they want to use one for internet but still be able to ping over the VPN to the other side. The CPN will only be accessable if the default gateway for the PCs is the Cisco becuase the Sonicwall knows nothing about the VPN ip range. The sonicwall needs a static router adding to say for this ip range go to this gateway.

read the first post,

I have my modem then a switch, and two gateways a Cisco 800, and a sonicwall tz170.


So in-other words what i said might just work.
 
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