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How to access a separate network on our LAN

We have a data collection network ( that is separate from our primary LAN (  We have a single computer with two Ethernet cards that is connected to both networks.  We are trying to configure it so that other computers on the LAN can "see" devices on the other network.

I think we need to configure some sort of bridge.  But when we do that it doesn't work?  I've never set up a bridge.  What am I missing?
Kerry Wilson
Kerry Wilson
1 Solution
Hate to nit-pick your language but...

What you are looking for is a router which functions at layer 3 of OSI (network layer).  Layer 1 is physical (think wire - could be shielded twisted pair cat-5 - or some other media).  Layer 2 is data layer - how you share the media. In most cases this would be ethernet.  Layer 3 is the network layer where IP comes into play with 32 bit addresses (which you wrote as  The IP addresses are on different IP networks (from the /24) so a router would need to be installed.

I'm not intimately familiar with what the current state of software based routers are in the Windows world, but you used to be able to do it with "remote and routing access services".  Not sure if that still exists, or if Microsoft renamed it.

Good luck.
I agree with the above that you require a software router, you could use routing and remote access available in Windows. It all depends on how much you really wish to do with this machine, if it is to simply act as a router in between networks you could use a distro such as pfsense (http://www.pfsense.org/) or simmilar.

Pfsense does provides lots of functionality past simply routing across networks however it is a dedicated router style os so would be perfect for this task.

If I can provide any further info or assistance in your setup please let me know ;)

Good luck.
you do not need a bridge, you need a router.

any machine can act as a router

in windows prior to seven, you need to set
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\ Services\Tcpip\Parameters\IPEnableRouter to a dword with value 1

in seven and above, either use the above or start the "routing and ..." service from services.msc

in linux use either
sysctl -w net.ipv4.ip_forward=1
echo 1 > /proc/sys/net/ipv4/ip_forward
(set it permanently in syscl.conf)

on freebsd, you'd add router_enable=yes to your r.conf file

on ... what do you use ?
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You've mentioned nothing in terms of how the network itself is structured. You have two LANs, but are you using two different WAN connections, or do you have two separate routers? Please clarify that side of it.... you would be able to simple use something like a Sonicwall, and define two different LANs.
i forgot to state that once you setup the machine properly, it will work if and only if either that router is the default gateway of your machines, or your machines are setup with static routes that tell them to go through that host when they want to reach the other network
Kerry WilsonAuthor Commented:
I have set the IPEnableRouter to '1' as suggested.  I have set a static route on my computer 'ROUTE ADD MASK' where the other network is 192.168.10.xxx and the machine sitting between both networks is on my side and on the other side.

However, I am still not able to ping the other network devices.  Not sure where to go from here.  (Note: when on the machine between the two networks I am able to ping devices on the data collection network...so I know they are responding to the ICMP request).
did you create the equivalent route on the other side ?
something like this should do
route add mask

you need both routes for ping to work.
also make sure you don't have a firewall or some kind of "anti-virus suite" which usually contain personal firewalls on that host.
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