I have two subnets which I am interested in connecting. I've read from beginning to the Linux Networking HOWTO, a few guides here on nixCraft, many forums posts, but have so far succeeded only in confusing myself.

Some basic network details:

Subnet A:
Network Range: 192.168.1.0/24
Gateway 1A: 192.168.1.1/255.255.255.0
Gateway Interfaces:
br0: 192.168.1.1/255.255.255.0
vlan1: 70.76.84.224/255.255.252.0
LAN Domain: tec.lan
Example Host 1A: perpetrator.tec.lan - 192.168.1.10/255.255.255.0
Example Host 2A: rapine.tec.lan - 192.168.1.11/255.255.255/0

Subnet B:
Network Range: 192.168.2.0/24
Gateway 1B: 192.168.2.1/255.255.255.0
Gateway Interfaces:
eth0: 192.168.1.145/255.255.255.0
eth1: 192.168.2.1/255.255.255.0
LAN Domain: tec.lan
Example Host 1B: ubuntu-01.tec.lan - 192.168.2.10/255.255.255.0
Example Host 2B: ubuntu-02.tec.lan - 192.168.2.11/255.255.255.0


I am trying to think of any further relevant details, but that seems to be it to me. If I forgot anything, please tell me.

Ok the question. WHAT do I type? (Explicitly!) And WHERE do I type it? In order to reach ubuntu-01.tec.lan, or ubuntu-02.tec.lan from perpetrator.tec.lan or rapine.tec.lan?

Note: I'm interested in using actuall ROUTES. I can already achieve results similair to this with either a NAT firewall, or with VPN.. but that's not what I am interested in.

Thank you very much for your reads and help in advance! This seems like it should be a simple thing, but I am having incredible difficulty with this..

From what I have found out so far, I should need something like the following:

On Gateway 1B:
And on Gateway 1A:
Any help would be appreciated!

your "subnets" make no sense at all. Since when did a subnet contain NIC's???

If you want to networks to be able to communicate then you need a common device on that network, and for all nodes to know to use that intermediate device to get there. You do not need to change any routes on the "gateway" device as that is already fully aware of both subnets by virtue of being connected to them, so it is all the clients that need to be told. That is unless this connecting gateway is already the default gateway in which case it's implicit. You then would need to ensure that the gateway device is configured to route the traffic, under linux this is just a case of running "echo 1 > /proc/sys/net/ipv4/ip_forward"

Ok, perhaps I should have labeled them Network A and Network B then. Sorry for the improper terminology

To clarify what it is I am trying to do here a bit.. I have a standard network (192.168.1.0/24) consisting of multiple computers and a DD-WRT router. Then in addition to these normal resources, I have a Host-Only Virtual network running a series of virtual machines. Those virtual machines are on the 192.168.2.0/24 ip range. I simply wish to be able to make my virtual machines aware of the normal, non-virtual network without resorting to Network Address Translation or any kind of VPN solution.

That said, your (acid_kewpie) reply has not been of any help. Could you perhaps try to clarify a bit more now that my intent is hopefully more clear?

Thanks for the reply though Acid, I really appreciate it!

This post http://www.linuxquestions.org/questi...ml#post3877086 might be useful to you. As a matter of fact I am routing 3 subnets or so, you have to skip things which are related to the 3rd subnet only.

jlinkels

1 members found this post helpful.

Oh that looks very usefull! Diagrams and everything! Those help SO much! *grins* thanks jlinkels. Wish me luck! I'll post success or failure here later. That looks like some quality instructions and clarifications, thanks a bunch for the help.

Just an update.. I have it all working perfectly now. The correct answer was:

1. Tell the machines on Subnet B to use 192.168.2.1 as their gateway, and:

2. On Gateway 1A, configure a static route telling packets trying to reach 192.168.2.0/24 to use 192.168.1.145 as their gateway.

Thank you for your time.