Re: Cross Subnet Connections

George wrote:
Tauno Voipio wrote:

George wrote:

Hope this isn't a stupid question!

I have a large private network with several subnets operating on it.
They are in the 10.x.x.x ranges. I have a central proxy that gives connections to the internet on one subnet, which all the others can connect to. I then have two computers, one with ip address 10.4.2.52 and one with ip 10.5.2.76.
These two computers are both able to access the internet through the proxy, but they cannot communicate directly with each other. I am planning to make an application that would require either tcp or udp communication between them, however, i do not have access to the proxy or any of the routers! Is there a way of making a connection between them, or is it simply impossible.

George



We should need a working crystal ball to respond.

You left out the absolutely necessary details:

- which operating system on both affected hosts,
- what is the current network set-up, subnets & masks,
- are the affected computers in the same Ethernet physically,
- is the proxy host forwarding HTTP only,
- are you thinking of having the connection via the proxy host,
- how is routing set up at the affected hosts and at the proxy host,
- is there a packet filter (firewall) in the hosts,
- if there is the packet filter, what is its set-up.


- OS - both linux boxes

Which distribution and kernel versions (use 'uname -a')?

Is the proxy box also a Linux box? If not, what?

- all have subnet masks 255.255.255.0 - not quite sure what the actual subnet values are that you requested... (I'm not very hot on networking, as you can see!)

So there are at least subnets 10.4.2.0/24 and 10.5.2.0/24.

- Both computers are behind separate routers, but the routers are both connected to one further hub, which the proxy is also connected to.

Which kind of routers?

- proxy is only forwarding http, as far as I can tell, however i would like to avoid getting it involved if at all possible.

How is the proxy connected to the rest of the net?

- routing - I'm not sure how to find out...

On each Linux machine, type:

route -n

and post the result.

- neither of the machines are firewalled.

Depending on kernel version, type:

ipchains -n -L -v

or

iptables -n -L -v

and post the responses.

Hope these details make it a bit clearer...

You're still very quiet on the real details, but
maybe we can fish them out ...

--

Tauno Voipio
tauno voipio (at) iki fi
.

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