Bridging and Routing...

[SteveC]

How??!??!?

Right, imagine this:

<IMG SRC="http://www.steve-cooper.co.uk/murc/bridge.gif">

At work we have a (old, well over used) Token Ring Network, and I've put a few machines onto my own 100mbps ethernet so that traffic between my local machines is nice and fast. However, I need to bridge the two networks so that my ethernet PCs can access the token ring machines.

I have 1 PC which has both network cards in, and if I run win2k on it, and use the inbuilt internet connection sharing, I can access the token ring PCs via IP addresses, but not by their PC names. Also, the token ring machines cannot 'see' my ethernet at all. This is to be expected as all I'm doing is using the ICS' NAT one way from ethernet to token ring.

What I want to do is bridge the networks more properly, but I haven't a clue on how to go about doing this. I see win2k server has a 'bridging and routing' something or other, but I can't work out what to do.

Any ideas/good resources/comments?

[Dilitante1]

you cant call up the token ring PCs by name without WINS on the LAN if I remember right.....


Greebe usually recommends:

http://www.practicallynetworked.com/

I'll keep looking tho.....

-Dil

[Helevitia]

Hi Steve,

It can't be done unless Windows2K supports(which I highly doubt) some kind of Translational bridging or Source-Route Transparent bridging. You would need a device, such as a router or bridge, that is capable of this. Here is a link for you to indulge in.

http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/mmbridge.htm#17389

Dave

[Rags]

Nevermind, stupid idea by me.

Rags

[Helevitia]

hmmm...I was thinking about why you are able to talk to the machines via IP address and thought that windows must be doing some kind of packet juggling. I twould have to strip the data from the packet and form a new TokenRing packet and send it on it's merry way. After more thought, I dont think this is happening. The clue was "internet sharing". I think what is happening is the internet sharing is sending the packet out to your default gateway(router) and the router is sending it back to the win2k machine. hmmm...either way it has to strip the data and repackage it. hmmm...?

Dave

[Marshmallowman]

can't you do netbios name matching to IP in their "HOSTS" files?

mumble,mumble..linux..mumble

[SteveC]

Originally posted by Marshmallowman
can't you do netbios name matching to IP in their "HOSTS" files?

mumble,mumble..linux..mumble

Yes, that does work so that the ethernet PCs can see the T/R PCs, however, because the internet connection sharing is only 'one-way' as such, PCs on the token ring can't see PCs on the ethernet.

Have to do more research, I've built me a high quality win2k machine to play with (was going to be a P100 with 32Mb RAM, but it wouldn't install , so I've found a PII-350, 128Mb, but a massive 1Gig hard drive! wow )

[SteveC]

Oh, and the reason I think win2k can do it, is that the inbuilt 'routing and remote access' thingy, says this:

<B>Routing and Remote Access
The Microsoft Windows 2000 Server Routing and Remote Access service provides:

Multiprotocol LAN-to-LAN, LAN-to-WAN, virtual private network (VPN), and network address translation (NAT) routing services.

Dial-up and VPN remote access services. </B>

I guess I'll just have to wade through microsoft's site till I find something that makes sense.... I take it no one here's used this part of win2k server then?

[Taz]

One of our clients, a German Bank, had the same problem in that they were migrating from token ring to ethernet but the routers which connect them to their other offices were on the token ring side but needed to be access by both sides. They wanted the IP to be bridged rather than routed which doesn't leave many options. The only product we could find to do this was a 3Com NetBuilder router fitted with ethernet and token ring cards, this was incredibly expensive If you can get away with routing rather than bridging there are a lot cheaper solutions.

[SteveC]

I got it working! Win2k's routing and remote access software lets you set up NATs and the like and so now, I have the following:


Token Ring LAN for all internal traffic around the company

Local Ethernet LAN for the local few machines

Live Ethernet LAN which is connected straight to the Pipex 2mb leased line



So now, when PCs on my local ethernet want token ring access, they get routed through the token ring card, and when they want internet, they go through the live ethernet card What made it confusing is that the token ring <I>also</I> goes through to the live ethernet at a firewall, but I wanted to skip this as the token ring is so slow.

But still, although PCs on the local ethernet see everything fine, it doesn't work the other way - token ring machines can't see the local ethernet. However, I can set up port forwarding from the token ring to the local ethernet so I can access a webserver or whatever on the local ethernet from the token ring.

(I think that makes sense )

[EdSki]

Steve,

The tricky part is the routing tables on the token ring machines. You can set up the multihomed machine as a router between your two networks (regular routing, not NAT), but these machines will send ip adresses wich are not part of there own segment to their configured gateway (internet router/firewall?, reading your post i assume you are on two ip subnets, one for tokenring and one for ethernet). The gateway is probably assigned by dhcp? Port forwarding isn't ideal, you would need to map netbios ports to multiple computers, that won't work i think. ( a quick edit was necessary here )

I assume you can't have an entry on the Tokenring-gateway's routing table added for your ethernet subnet, pointing to your win2k router? (Where i work this would be a mission impossible)

Then one thing you could try is adding an entry for your ethernet subnet on all the tokenring machines you want to connect to your ethernet network pointing to your win2k router (I hope not all of them).

I think all your other options are a regular bridge or big changes to the setup of your network (ethernet AND tokenring)..

Or offcourse somebody else has to come up with a smart solution i didn't think off, i don't deal with sort of thing much..

Grtz,
Ed